[ { "sku": "81102-TN", "brand": "SKF", "manufacturer_designation": "81102 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 15, "D_mm": 28, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 11.2, "static_load_kN": 27, "fatigue_load_limit_kN": 2.45, "reference_speed_rpm": 4300, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 24, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81102 TN as a separable thrust bearing: the 15 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 28 mm housing washer (GS) can be ordered and mounted individually. In 81102 TN, 811 fixes the 28 mm OD and 9 mm height; 02 selects the 15 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 9 mm height. Minimum axial load is explicit at factor A 5.80e-5: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Mounting: locate the shaft washer on the 15 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 28 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At a 15 mm seat the 9 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 5.80e-5 as the floor.", "Factor A 5.80e-5 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81102 TN size.", "the 4,300 r/min reference speed is the thermal criterion under load, the 8,500 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 11.2/27 kN ratings and 24 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 81102 TN?", "a": "A 81102 TN measures 15 mm bore × 28 mm outside diameter × 9 mm width (0.591 × 1.102 × 0.354 in). From SKF catalogue PUB BU/P1 17000: dynamic C 11.2 kN, static C0 27 kN, fatigue limit Pu 2.45 kN, reference speed 4,300 r/min, limiting speed 8,500 r/min, mass about 24 g. Raceway diameters Ea 16 mm / Eb 27 mm and minimum load factor A 5.80e-5 guide the seat design." }, { "q": "How is the 81102 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 02 encodes the 15 mm bore (code 02 = 15 mm); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81102 TN need a minimum axial load?", "a": "Below factor A 5.80e-5 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81102 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "81102", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81102-TN", "81102 TN" ], "locale_variants": {} }, { "sku": "81103-TN", "brand": "SKF", "manufacturer_designation": "81103 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 17, "D_mm": 30, "B_mm": 9, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 12.2, "static_load_kN": 31.5, "fatigue_load_limit_kN": 2.85, "reference_speed_rpm": 4300, "limiting_speed_rpm": 8500, "max_rpm": 8500, "weight_g": 27, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81103 TN as a separable thrust bearing: the 17 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 30 mm housing washer (GS) can be ordered and mounted individually. In 81103 TN, 811 fixes the 30 mm OD and 9 mm height; 03 selects the 17 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Small sizes ship with glass-fibre PA66 TN cages for quiet, low-friction running; the 12.2 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 7.90e-5: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 7.90e-5) is present without clamping the rollers.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At a 17 mm seat the 9 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 7.90e-5 as the floor.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81103 TN need different minimum load and lubrication despite the shared 17×30 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81103 TN size.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "the 4,300 r/min reference speed is the thermal criterion under load, the 8,500 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 12.2/31.5 kN ratings and 27 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 81103 TN?", "a": "A 81103 TN measures 17 mm bore × 30 mm outside diameter × 9 mm width (0.669 × 1.181 × 0.354 in). From SKF catalogue PUB BU/P1 17000: dynamic C 12.2 kN, static C0 31.5 kN, fatigue limit Pu 2.85 kN, reference speed 4,300 r/min, limiting speed 8,500 r/min, mass about 27 g. Raceway diameters Ea 18 mm / Eb 29 mm and minimum load factor A 7.90e-5 guide the seat design." }, { "q": "How is the 81103 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 03 encodes the 17 mm bore (code 03 = 17 mm); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81103 TN need a minimum axial load?", "a": "Below factor A 7.90e-5 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81103 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "81103", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81103-TN", "81103 TN" ], "locale_variants": {} }, { "sku": "81104-TN", "brand": "SKF", "manufacturer_designation": "81104 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 20, "D_mm": 35, "B_mm": 10, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 18.6, "static_load_kN": 48, "fatigue_load_limit_kN": 4.65, "reference_speed_rpm": 3800, "limiting_speed_rpm": 7500, "max_rpm": 7500, "weight_g": 37, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81104 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 20×35×10 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81104 TN sits in the light 811 series. Small sizes ship with glass-fibre PA66 TN cages for quiet, low-friction running; the 18.6 kN rating assumes oil or grease reaching the full washer face. Selection arithmetic: C 18.6 kN against C0 48 kN gives a C0/C ratio of 2.58 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At a 20 mm seat the 10 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 1.80e-4 as the floor.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81104 TN size.", "the 3,800 r/min reference speed is the thermal criterion under load, the 7,500 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 18.6/48 kN ratings assume flat, full-support washer seats; a housing face narrower than the 35 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81104 TN need different minimum load and lubrication despite the shared 20×35 mm outline.", "The 18.6/48 kN ratings and 37 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81104 TN in service?", "a": "Unloaded running below factor A 1.80e-4 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 7,500 r/min limiting." }, { "q": "Which dimensions does the 81104 TN have?", "a": "A 81104 TN measures 20 mm bore × 35 mm outside diameter × 10 mm width (0.787 × 1.378 × 0.394 in). From SKF catalogue PUB BU/P1 17000: dynamic C 18.6 kN, static C0 48 kN, fatigue limit Pu 4.65 kN, reference speed 3,800 r/min, limiting speed 7,500 r/min, mass about 37 g. Raceway diameters Ea 21 mm / Eb 34 mm and minimum load factor A 1.80e-4 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81104 TN belongs to the light 811 series, 20×35×10 mm." }, { "q": "Are the washers of 81104 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81104", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81104-TN", "81104 TN" ], "locale_variants": {} }, { "sku": "81105-TN", "brand": "SKF", "manufacturer_designation": "81105 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 25, "D_mm": 42, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 25, "static_load_kN": 69.5, "fatigue_load_limit_kN": 6.8, "reference_speed_rpm": 3200, "limiting_speed_rpm": 6300, "max_rpm": 6300, "weight_g": 53, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81105 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 25×42×11 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81105 TN sits in the light 811 series. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 11 mm height. Selection arithmetic: C 25 kN against C0 69.5 kN gives a C0/C ratio of 2.78 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Mounting: locate the shaft washer on the 25 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 42 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At a 25 mm seat the 11 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 3.90e-4 as the floor.", "The 25/69.5 kN ratings assume flat, full-support washer seats; a housing face narrower than the 42 mm washer OD invalidates the rating through edge stress.", "Factor A 3.90e-4 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81105 TN need different minimum load and lubrication despite the shared 25×42 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81105 TN size.", "The 25/69.5 kN ratings and 53 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81105 TN in service?", "a": "Unloaded running below factor A 3.90e-4 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 6,300 r/min limiting." }, { "q": "Which dimensions does the 81105 TN have?", "a": "A 81105 TN measures 25 mm bore × 42 mm outside diameter × 11 mm width (0.984 × 1.654 × 0.433 in). From SKF catalogue PUB BU/P1 17000: dynamic C 25 kN, static C0 69.5 kN, fatigue limit Pu 6.8 kN, reference speed 3,200 r/min, limiting speed 6,300 r/min, mass about 53 g. Raceway diameters Ea 26 mm / Eb 41 mm and minimum load factor A 3.90e-4 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81105 TN belongs to the light 811 series, 25×42×11 mm." }, { "q": "Are the washers of 81105 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81105", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81105-TN", "81105 TN" ], "locale_variants": {} }, { "sku": "81106-TN", "brand": "SKF", "manufacturer_designation": "81106 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 30, "D_mm": 47, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 27, "static_load_kN": 78, "fatigue_load_limit_kN": 7.65, "reference_speed_rpm": 3000, "limiting_speed_rpm": 6000, "max_rpm": 6000, "weight_g": 57, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81106 TN replaces the ball complement with cylindrical rollers: 30 mm bore, 47 mm OD, rated 78 kN static for steady hook and screw loads. The designation 81106 TN states 811 series, 30 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 4.90e-4. One direction only: 81106 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At a 30 mm seat the 11 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 4.90e-4 as the floor.", "Factor A 4.90e-4 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81106 TN need different minimum load and lubrication despite the shared 30×47 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81106 TN size.", "The 27/78 kN ratings and 57 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81106 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 4.90e-4 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81106 TN?", "a": "A 81106 TN measures 30 mm bore × 47 mm outside diameter × 11 mm width (1.181 × 1.85 × 0.433 in). From SKF catalogue PUB BU/P1 17000: dynamic C 27 kN, static C0 78 kN, fatigue limit Pu 7.65 kN, reference speed 3,000 r/min, limiting speed 6,000 r/min, mass about 57 g. Raceway diameters Ea 31 mm / Eb 46 mm and minimum load factor A 4.90e-4 guide the seat design." }, { "q": "How is the 81106 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 06 encodes the 30 mm bore (code 06 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81106 TN need a minimum axial load?", "a": "Below factor A 4.90e-4 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81106", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81106-TN", "81106 TN" ], "locale_variants": {} }, { "sku": "81206-TN", "brand": "SKF", "manufacturer_designation": "81206 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 30, "D_mm": 52, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 50, "static_load_kN": 134, "fatigue_load_limit_kN": 13.4, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4800, "max_rpm": 4800, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The heavy 812 series bearing 81206 TN carries pure axial load at low to moderate speed: 50 kN dynamic and 134 kN static across a 30×52 mm washer pair, 16 mm overall height. The designation 81206 TN states 812 series, 30 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Minimum axial load is explicit at factor A 0.0014: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Mounting: locate the shaft washer on the 30 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 52 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At a 30 mm seat the 16 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 0.0014 as the floor.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81206 TN need different minimum load and lubrication despite the shared 30×52 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81206 TN size.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "the 2,400 r/min reference speed is the thermal criterion under load, the 4,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 50/134 kN ratings and 120 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81206 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 06 encodes the 30 mm bore (code 06 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81206 TN need a minimum axial load?", "a": "Below factor A 0.0014 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81206 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81206 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0014 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81206", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81206-TN", "81206 TN" ], "locale_variants": {} }, { "sku": "81107-TN", "brand": "SKF", "manufacturer_designation": "81107 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 35, "D_mm": 52, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 29, "static_load_kN": 93, "fatigue_load_limit_kN": 9.15, "reference_speed_rpm": 2800, "limiting_speed_rpm": 5600, "max_rpm": 5600, "weight_g": 73, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81107 TN is the rigid-washer thrust solution for a 35 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 29 kN C within just 12 mm of axial space, per the ISO 104 plan. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 07 encode the 35 mm shaft washer bore (code 07 × 5), and TN names the cage execution. Small sizes ship with glass-fibre PA66 TN cages for quiet, low-friction running; the 29 kN rating assumes oil or grease reaching the full washer face. Static safety matters for shock duty: compare peak axial force against C0 93 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 6.90e-4) is present without clamping the rollers.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At a 35 mm seat the 12 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 6.90e-4 as the floor.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81107 TN need different minimum load and lubrication despite the shared 35×52 mm outline.", "the 2,800 r/min reference speed is the thermal criterion under load, the 5,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 29/93 kN ratings assume flat, full-support washer seats; a housing face narrower than the 52 mm washer OD invalidates the rating through edge stress.", "The 29/93 kN ratings and 73 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81107 TN in service?", "a": "Unloaded running below factor A 6.90e-4 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 5,600 r/min limiting." }, { "q": "Which dimensions does the 81107 TN have?", "a": "A 81107 TN measures 35 mm bore × 52 mm outside diameter × 12 mm width (1.378 × 2.047 × 0.472 in). From SKF catalogue PUB BU/P1 17000: dynamic C 29 kN, static C0 93 kN, fatigue limit Pu 9.15 kN, reference speed 2,800 r/min, limiting speed 5,600 r/min, mass about 73 g. Raceway diameters Ea 36 mm / Eb 51 mm and minimum load factor A 6.90e-4 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81107 TN belongs to the light 811 series, 35×52×12 mm." }, { "q": "Are the washers of 81107 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81107", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81107-TN", "81107 TN" ], "locale_variants": {} }, { "sku": "81207-TN", "brand": "SKF", "manufacturer_designation": "81207 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 35, "D_mm": 62, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 62, "static_load_kN": 190, "fatigue_load_limit_kN": 19.3, "reference_speed_rpm": 2000, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81207 TN as a separable thrust bearing: the 35 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 62 mm housing washer (GS) can be ordered and mounted individually. The designation 81207 TN states 812 series, 35 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 18 mm height. Minimum axial load is explicit at factor A 0.0029: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At a 35 mm seat the 18 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 0.0029 as the floor.", "the 2,000 r/min reference speed is the thermal criterion under load, the 4,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 62/190 kN ratings assume flat, full-support washer seats; a housing face narrower than the 62 mm washer OD invalidates the rating through edge stress.", "Factor A 0.0029 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81207 TN need different minimum load and lubrication despite the shared 35×62 mm outline.", "The 62/190 kN ratings and 210 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81207 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 07 encodes the 35 mm bore (code 07 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81207 TN need a minimum axial load?", "a": "Below factor A 0.0029 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81207 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81207 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0029 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81207", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81207-TN", "81207 TN" ], "locale_variants": {} }, { "sku": "81108-TN", "brand": "SKF", "manufacturer_designation": "81108 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 40, "D_mm": 60, "B_mm": 13, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 43, "static_load_kN": 137, "fatigue_load_limit_kN": 13.7, "reference_speed_rpm": 2400, "limiting_speed_rpm": 5000, "max_rpm": 5000, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81108 TN is the rigid-washer thrust solution for a 40 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 43 kN C within just 13 mm of axial space, per the ISO 104 plan. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 08 encode the 40 mm shaft washer bore (code 08 × 5), and TN names the cage execution. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 13 mm height. Static safety matters for shock duty: compare peak axial force against C0 137 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At a 40 mm seat the 13 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 0.0015 as the floor.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81108 TN size.", "the 2,400 r/min reference speed is the thermal criterion under load, the 5,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81108 TN need different minimum load and lubrication despite the shared 40×60 mm outline.", "The 43/137 kN ratings assume flat, full-support washer seats; a housing face narrower than the 60 mm washer OD invalidates the rating through edge stress.", "The 43/137 kN ratings and 110 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81108 TN in service?", "a": "Unloaded running below factor A 0.0015 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 5,000 r/min limiting." }, { "q": "Which dimensions does the 81108 TN have?", "a": "A 81108 TN measures 40 mm bore × 60 mm outside diameter × 13 mm width (1.575 × 2.362 × 0.512 in). From SKF catalogue PUB BU/P1 17000: dynamic C 43 kN, static C0 137 kN, fatigue limit Pu 13.7 kN, reference speed 2,400 r/min, limiting speed 5,000 r/min, mass about 110 g. Raceway diameters Ea 42 mm / Eb 58 mm and minimum load factor A 0.0015 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81108 TN belongs to the light 811 series, 40×60×13 mm." }, { "q": "Are the washers of 81108 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81108", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81108-TN", "81108 TN" ], "locale_variants": {} }, { "sku": "81208-TN", "brand": "SKF", "manufacturer_designation": "81208 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 40, "D_mm": 68, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 83, "static_load_kN": 255, "fatigue_load_limit_kN": 26.5, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81208 TN as a separable thrust bearing: the 40 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 68 mm housing washer (GS) can be ordered and mounted individually. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 08 encode the 40 mm shaft washer bore (code 08 × 5), and TN names the cage execution. Small sizes ship with glass-fibre PA66 TN cages for quiet, low-friction running; the 83 kN rating assumes oil or grease reaching the full washer face. Speed planning separates the 1,900 r/min thermal reference from the 3,800 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 40 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 68 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At a 40 mm seat the 19 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 0.0052 as the floor.", "The 83/255 kN ratings assume flat, full-support washer seats; a housing face narrower than the 68 mm washer OD invalidates the rating through edge stress.", "Factor A 0.0052 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81208 TN size.", "the 1,900 r/min reference speed is the thermal criterion under load, the 3,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 83/255 kN ratings and 250 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81208 TN belongs to the heavy 812 series, 40×68×19 mm." }, { "q": "Are the washers of 81208 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81208 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81208 TN in service?", "a": "Unloaded running below factor A 0.0052 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 3,800 r/min limiting." } ], "cross_ref": [ { "equiv_sku": "81208", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81208-TN", "81208 TN" ], "locale_variants": {} }, { "sku": "89308-TN", "brand": "SKF", "manufacturer_designation": "89308 TN", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 40, "D_mm": 78, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 95, "static_load_kN": 365, "fatigue_load_limit_kN": 36.5, "reference_speed_rpm": 2000, "limiting_speed_rpm": 4000, "max_rpm": 4000, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "89308 TN is the rigid-washer thrust solution for a 40 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 95 kN C within just 22 mm of axial space, per the ISO 104 plan. In 89308 TN, 893 fixes the 78 mm OD and 22 mm height; 08 selects the 40 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 22 mm height. Speed planning separates the 2,000 r/min thermal reference from the 4,000 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 40 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 78 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At a 40 mm seat the 22 mm stack is easy to over-clamp — a cover torqued solid removes all roller clearance; shim to the catalogue endplay and keep factor A 0.011 as the floor.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89308 TN need different minimum load and lubrication despite the shared 40×78 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89308 TN size.", "Factor A 0.011 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 95/365 kN ratings and 480 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 89308 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 89308 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.011 minimum load is present." }, { "q": "What are the dimensions and ratings of the 89308 TN?", "a": "A 89308 TN measures 40 mm bore × 78 mm outside diameter × 22 mm width (1.575 × 3.071 × 0.866 in). From SKF catalogue PUB BU/P1 17000: dynamic C 95 kN, static C0 365 kN, fatigue limit Pu 36.5 kN, reference speed 2,000 r/min, limiting speed 4,000 r/min, mass about 480 g. Raceway diameters Ea 44 mm / Eb 77 mm and minimum load factor A 0.011 guide the seat design." }, { "q": "How is the 89308 TN designation read?", "a": "The first three digits 893 give the dimension series (heavy 893 series); 08 encodes the 40 mm bore (code 08 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "89308", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89308-TN", "89308 TN" ], "locale_variants": {} }, { "sku": "81109-TN", "brand": "SKF", "manufacturer_designation": "81109 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 45, "D_mm": 65, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 45, "static_load_kN": 153, "fatigue_load_limit_kN": 15.3, "reference_speed_rpm": 2200, "limiting_speed_rpm": 4500, "max_rpm": 4500, "weight_g": 130, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 81109 TN denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.0019. In 81109 TN, 811 fixes the 65 mm OD and 14 mm height; 09 selects the 45 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.0019. The 130 g mass and 14 mm axial height sit between 45 and 65 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.0019) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "grease churning and overheating when a high-speed thrust position is over-packed", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 45 mm bore the minimum load (A 0.0019) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 2,200 r/min reference speed is the thermal criterion under load, the 4,500 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 45/153 kN ratings assume flat, full-support washer seats; a housing face narrower than the 65 mm washer OD invalidates the rating through edge stress.", "Factor A 0.0019 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 45/153 kN ratings and 130 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81109 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0019 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81109 TN?", "a": "A 81109 TN measures 45 mm bore × 65 mm outside diameter × 14 mm width (1.772 × 2.559 × 0.551 in). From SKF catalogue PUB BU/P1 17000: dynamic C 45 kN, static C0 153 kN, fatigue limit Pu 15.3 kN, reference speed 2,200 r/min, limiting speed 4,500 r/min, mass about 130 g. Raceway diameters Ea 47 mm / Eb 63 mm and minimum load factor A 0.0019 guide the seat design." }, { "q": "How is the 81109 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 09 encodes the 45 mm bore (code 09 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81109 TN need a minimum axial load?", "a": "Below factor A 0.0019 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81109", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81109-TN", "81109 TN" ], "locale_variants": {} }, { "sku": "81209-TN", "brand": "SKF", "manufacturer_designation": "81209 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 45, "D_mm": 73, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 83, "static_load_kN": 255, "fatigue_load_limit_kN": 26.5, "reference_speed_rpm": 1800, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 290, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81209 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 45×73×20 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 09 encode the 45 mm shaft washer bore (code 09 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Speed planning separates the 1,800 r/min thermal reference from the 3,600 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 45 mm bore the minimum load (A 0.0052) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81209 TN need different minimum load and lubrication despite the shared 45×73 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81209 TN size.", "the 1,800 r/min reference speed is the thermal criterion under load, the 3,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 83/255 kN ratings and 290 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81209 TN belongs to the heavy 812 series, 45×73×20 mm." }, { "q": "Are the washers of 81209 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81209 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81209 TN in service?", "a": "Unloaded running below factor A 0.0052 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 3,600 r/min limiting." } ], "cross_ref": [ { "equiv_sku": "81209", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81209-TN", "81209 TN" ], "locale_variants": {} }, { "sku": "81110-TN", "brand": "SKF", "manufacturer_designation": "81110 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 50, "D_mm": 70, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 47.5, "static_load_kN": 166, "fatigue_load_limit_kN": 16.6, "reference_speed_rpm": 2200, "limiting_speed_rpm": 4300, "max_rpm": 4300, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81110 TN as a separable thrust bearing: the 50 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 70 mm housing washer (GS) can be ordered and mounted individually. The designation 81110 TN states 811 series, 50 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Speed planning separates the 2,200 r/min thermal reference from the 4,300 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 50 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 70 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 50 mm bore the minimum load (A 0.0022) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81110 TN need different minimum load and lubrication despite the shared 50×70 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81110 TN size.", "Factor A 0.0022 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 47.5/166 kN ratings and 140 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81110 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 10 encodes the 50 mm bore (code 10 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81110 TN need a minimum axial load?", "a": "Below factor A 0.0022 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81110 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81110 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0022 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81110", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81110-TN", "81110 TN" ], "locale_variants": {} }, { "sku": "81210-TN", "brand": "SKF", "manufacturer_designation": "81210 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 50, "D_mm": 78, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 91.5, "static_load_kN": 300, "fatigue_load_limit_kN": 31, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81210 TN is the rigid-washer thrust solution for a 50 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 91.5 kN C within just 22 mm of axial space, per the ISO 104 plan. The designation 81210 TN states 812 series, 50 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.0072. Static safety matters for shock duty: compare peak axial force against C0 300 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.0072) is present without clamping the rollers.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 50 mm bore the minimum load (A 0.0072) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 1,700 r/min reference speed is the thermal criterion under load, the 3,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 91.5/300 kN ratings assume flat, full-support washer seats; a housing face narrower than the 78 mm washer OD invalidates the rating through edge stress.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81210 TN need different minimum load and lubrication despite the shared 50×78 mm outline.", "The 91.5/300 kN ratings and 360 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81210 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81210 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0072 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81210 TN?", "a": "A 81210 TN measures 50 mm bore × 78 mm outside diameter × 22 mm width (1.969 × 3.071 × 0.866 in). From SKF catalogue PUB BU/P1 17000: dynamic C 91.5 kN, static C0 300 kN, fatigue limit Pu 31 kN, reference speed 1,700 r/min, limiting speed 3,400 r/min, mass about 360 g. Raceway diameters Ea 53 mm / Eb 75 mm and minimum load factor A 0.0072 guide the seat design." }, { "q": "How is the 81210 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 10 encodes the 50 mm bore (code 10 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81210", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81210-TN", "81210 TN" ], "locale_variants": {} }, { "sku": "81111-TN", "brand": "SKF", "manufacturer_designation": "81111 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 55, "D_mm": 78, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 69.5, "static_load_kN": 285, "fatigue_load_limit_kN": 29, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3800, "max_rpm": 3800, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81111 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 55×78×16 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 11 encode the 55 mm shaft washer bore (code 11 × 5), and TN names the cage execution. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 16 mm height. Selection arithmetic: C 69.5 kN against C0 285 kN gives a C0/C ratio of 4.10 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 55 mm bore the minimum load (A 0.0065) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81111 TN size.", "the 1,900 r/min reference speed is the thermal criterion under load, the 3,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 69.5/285 kN ratings assume flat, full-support washer seats; a housing face narrower than the 78 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81111 TN need different minimum load and lubrication despite the shared 55×78 mm outline.", "The 69.5/285 kN ratings and 230 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81111 TN belongs to the light 811 series, 55×78×16 mm." }, { "q": "Are the washers of 81111 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81111 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81111 TN in service?", "a": "Unloaded running below factor A 0.0065 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 3,800 r/min limiting." } ], "cross_ref": [ { "equiv_sku": "81111", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81111-TN", "81111 TN" ], "locale_variants": {} }, { "sku": "81211-TN", "brand": "SKF", "manufacturer_designation": "81211 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 55, "D_mm": 90, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 122, "static_load_kN": 390, "fatigue_load_limit_kN": 40, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 570, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 81211 TN denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.012. The designation 81211 TN states 812 series, 55 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 122 kN rating assumes oil or grease reaching the full washer face. Static safety matters for shock duty: compare peak axial force against C0 390 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: locate the shaft washer on the 55 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 90 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 55 mm bore the minimum load (A 0.012) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Factor A 0.012 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 122/390 kN ratings assume flat, full-support washer seats; a housing face narrower than the 90 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81211 TN need different minimum load and lubrication despite the shared 55×90 mm outline.", "The 122/390 kN ratings and 570 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81211 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81211 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.012 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81211 TN?", "a": "A 81211 TN measures 55 mm bore × 90 mm outside diameter × 25 mm width (2.165 × 3.543 × 0.984 in). From SKF catalogue PUB BU/P1 17000: dynamic C 122 kN, static C0 390 kN, fatigue limit Pu 40 kN, reference speed 1,400 r/min, limiting speed 2,800 r/min, mass about 570 g. Raceway diameters Ea 59 mm / Eb 85 mm and minimum load factor A 0.012 guide the seat design." }, { "q": "How is the 81211 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 11 encodes the 55 mm bore (code 11 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81211", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81211-TN", "81211 TN" ], "locale_variants": {} }, { "sku": "81112-TN", "brand": "SKF", "manufacturer_designation": "81112 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 60, "D_mm": 85, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 80, "static_load_kN": 300, "fatigue_load_limit_kN": 30.5, "reference_speed_rpm": 1800, "limiting_speed_rpm": 3600, "max_rpm": 3600, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81112 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 60×85×17 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 12 encode the 60 mm shaft washer bore (code 12 × 5), and TN names the cage execution. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 80 kN rating assumes oil or grease reaching the full washer face. Selection arithmetic: C 80 kN against C0 300 kN gives a C0/C ratio of 3.75 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Mounting: locate the shaft washer on the 60 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 85 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 60 mm bore the minimum load (A 0.0072) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The 80/300 kN ratings assume flat, full-support washer seats; a housing face narrower than the 85 mm washer OD invalidates the rating through edge stress.", "Factor A 0.0072 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81112 TN need different minimum load and lubrication despite the shared 60×85 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81112 TN size.", "The 80/300 kN ratings and 270 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81112 TN belongs to the light 811 series, 60×85×17 mm." }, { "q": "Are the washers of 81112 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81112 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81112 TN in service?", "a": "Unloaded running below factor A 0.0072 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 3,600 r/min limiting." } ], "cross_ref": [ { "equiv_sku": "81112", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81112-TN", "81112 TN" ], "locale_variants": {} }, { "sku": "81212-TN", "brand": "SKF", "manufacturer_designation": "81212 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 60, "D_mm": 95, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 137, "static_load_kN": 465, "fatigue_load_limit_kN": 47.5, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The heavy 812 series bearing 81212 TN carries pure axial load at low to moderate speed: 137 kN dynamic and 465 kN static across a 60×95 mm washer pair, 26 mm overall height. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 12 encode the 60 mm shaft washer bore (code 12 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. The 650 g mass and 26 mm axial height sit between 60 and 95 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 60 mm bore the minimum load (A 0.017) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81212 TN need different minimum load and lubrication despite the shared 60×95 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81212 TN size.", "the 1,400 r/min reference speed is the thermal criterion under load, the 2,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 137/465 kN ratings and 650 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81212 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81212 TN in service?", "a": "Unloaded running below factor A 0.017 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,800 r/min limiting." }, { "q": "Which dimensions does the 81212 TN have?", "a": "A 81212 TN measures 60 mm bore × 95 mm outside diameter × 26 mm width (2.362 × 3.74 × 1.024 in). From SKF catalogue PUB BU/P1 17000: dynamic C 137 kN, static C0 465 kN, fatigue limit Pu 47.5 kN, reference speed 1,400 r/min, limiting speed 2,800 r/min, mass about 650 g. Raceway diameters Ea 64 mm / Eb 91 mm and minimum load factor A 0.017 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81212 TN belongs to the heavy 812 series, 60×95×26 mm." } ], "cross_ref": [ { "equiv_sku": "81212", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81212-TN", "81212 TN" ], "locale_variants": {} }, { "sku": "89312-TN", "brand": "SKF", "manufacturer_designation": "89312 TN", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 60, "D_mm": 110, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 153, "static_load_kN": 640, "fatigue_load_limit_kN": 65.5, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "89312 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 893 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 60×110×30 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. In 89312 TN, 893 fixes the 110 mm OD and 30 mm height; 12 selects the 60 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 153 kN rating assumes oil or grease reaching the full washer face. The 1250 g mass and 30 mm axial height sit between 60 and 110 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.033) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "grease churning and overheating when a high-speed thrust position is over-packed", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 60 mm bore the minimum load (A 0.033) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 1,400 r/min reference speed is the thermal criterion under load, the 2,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 153/640 kN ratings assume flat, full-support washer seats; a housing face narrower than the 110 mm washer OD invalidates the rating through edge stress.", "Factor A 0.033 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 153/640 kN ratings and 1250 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 89312 TN?", "a": "A 89312 TN measures 60 mm bore × 110 mm outside diameter × 30 mm width (2.362 × 4.331 × 1.181 in). From SKF catalogue PUB BU/P1 17000: dynamic C 153 kN, static C0 640 kN, fatigue limit Pu 65.5 kN, reference speed 1,400 r/min, limiting speed 2,800 r/min, mass about 1250 g. Raceway diameters Ea 66 mm / Eb 108 mm and minimum load factor A 0.033 guide the seat design." }, { "q": "How is the 89312 TN designation read?", "a": "The first three digits 893 give the dimension series (heavy 893 series); 12 encodes the 60 mm bore (code 12 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 89312 TN need a minimum axial load?", "a": "Below factor A 0.033 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 89312 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "89312", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89312-TN", "89312 TN" ], "locale_variants": {} }, { "sku": "81113-TN", "brand": "SKF", "manufacturer_designation": "81113 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 65, "D_mm": 90, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 83, "static_load_kN": 320, "fatigue_load_limit_kN": 32.5, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81113 TN replaces the ball complement with cylindrical rollers: 65 mm bore, 90 mm OD, rated 320 kN static for steady hook and screw loads. In 81113 TN, 811 fixes the 90 mm OD and 18 mm height; 13 selects the 65 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. One direction only: 81113 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 65 mm bore the minimum load (A 0.0082) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Factor A 0.0082 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81113 TN need different minimum load and lubrication despite the shared 65×90 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81113 TN size.", "The 83/320 kN ratings and 310 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81113 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 13 encodes the 65 mm bore (code 13 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81113 TN need a minimum axial load?", "a": "Below factor A 0.0082 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81113 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81113 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.0082 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81113", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81113-TN", "81113 TN" ], "locale_variants": {} }, { "sku": "81213-TN", "brand": "SKF", "manufacturer_designation": "81213 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 65, "D_mm": 100, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 140, "static_load_kN": 490, "fatigue_load_limit_kN": 50, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 720, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The heavy 812 series bearing 81213 TN carries pure axial load at low to moderate speed: 140 kN dynamic and 490 kN static across a 65×100 mm washer pair, 27 mm overall height. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 13 encode the 65 mm shaft washer bore (code 13 × 5), and TN names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.019. The 720 g mass and 27 mm axial height sit between 65 and 100 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Mounting: locate the shaft washer on the 65 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 100 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 65 mm bore the minimum load (A 0.019) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81213 TN size.", "the 1,300 r/min reference speed is the thermal criterion under load, the 2,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81213 TN need different minimum load and lubrication despite the shared 65×100 mm outline.", "The 140/490 kN ratings and 720 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81213 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81213 TN in service?", "a": "Unloaded running below factor A 0.019 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,600 r/min limiting." }, { "q": "Which dimensions does the 81213 TN have?", "a": "A 81213 TN measures 65 mm bore × 100 mm outside diameter × 27 mm width (2.559 × 3.937 × 1.063 in). From SKF catalogue PUB BU/P1 17000: dynamic C 140 kN, static C0 490 kN, fatigue limit Pu 50 kN, reference speed 1,300 r/min, limiting speed 2,600 r/min, mass about 720 g. Raceway diameters Ea 69 mm / Eb 96 mm and minimum load factor A 0.019 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81213 TN belongs to the heavy 812 series, 65×100×27 mm." } ], "cross_ref": [ { "equiv_sku": "81213", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81213-TN", "81213 TN" ], "locale_variants": {} }, { "sku": "89313-TN", "brand": "SKF", "manufacturer_designation": "89313 TN", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 65, "D_mm": 115, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 153, "static_load_kN": 640, "fatigue_load_limit_kN": 65.5, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "max_rpm": 2800, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 89313 TN replaces the ball complement with cylindrical rollers: 65 mm bore, 115 mm OD, rated 640 kN static for steady hook and screw loads. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 89313 TN sits in the heavy 893 series. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Minimum axial load is explicit at factor A 0.033: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Mounting: locate the shaft washer on the 65 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 115 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 65 mm bore the minimum load (A 0.033) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The 153/640 kN ratings assume flat, full-support washer seats; a housing face narrower than the 115 mm washer OD invalidates the rating through edge stress.", "Factor A 0.033 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "the 1,400 r/min reference speed is the thermal criterion under load, the 2,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89313 TN need different minimum load and lubrication despite the shared 65×115 mm outline.", "The 153/640 kN ratings and 1350 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 89313 TN have?", "a": "A 89313 TN measures 65 mm bore × 115 mm outside diameter × 30 mm width (2.559 × 4.528 × 1.181 in). From SKF catalogue PUB BU/P1 17000: dynamic C 153 kN, static C0 640 kN, fatigue limit Pu 65.5 kN, reference speed 1,400 r/min, limiting speed 2,800 r/min, mass about 1350 g. Raceway diameters Ea 71 mm / Eb 113 mm and minimum load factor A 0.033 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89313 TN belongs to the heavy 893 series, 65×115×30 mm." }, { "q": "Are the washers of 89313 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 89313 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "89313", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89313-TN", "89313 TN" ], "locale_variants": {} }, { "sku": "81114-TN", "brand": "SKF", "manufacturer_designation": "81114 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 70, "D_mm": 95, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 86.5, "static_load_kN": 345, "fatigue_load_limit_kN": 34.5, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3400, "max_rpm": 3400, "weight_g": 330, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81114 TN is the rigid-washer thrust solution for a 70 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 86.5 kN C within just 18 mm of axial space, per the ISO 104 plan. In 81114 TN, 811 fixes the 95 mm OD and 18 mm height; 14 selects the 70 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Static safety matters for shock duty: compare peak axial force against C0 345 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: locate the shaft washer on the 70 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 95 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 70 mm bore the minimum load (A 0.0095) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81114 TN need different minimum load and lubrication despite the shared 70×95 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81114 TN size.", "the 1,700 r/min reference speed is the thermal criterion under load, the 3,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 86.5/345 kN ratings assume flat, full-support washer seats; a housing face narrower than the 95 mm washer OD invalidates the rating through edge stress.", "The 86.5/345 kN ratings and 330 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 81114 TN?", "a": "A 81114 TN measures 70 mm bore × 95 mm outside diameter × 18 mm width (2.756 × 3.74 × 0.709 in). From SKF catalogue PUB BU/P1 17000: dynamic C 86.5 kN, static C0 345 kN, fatigue limit Pu 34.5 kN, reference speed 1,700 r/min, limiting speed 3,400 r/min, mass about 330 g. Raceway diameters Ea 72 mm / Eb 92 mm and minimum load factor A 0.0095 guide the seat design." }, { "q": "How is the 81114 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 14 encodes the 70 mm bore (code 14 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81114 TN need a minimum axial load?", "a": "Below factor A 0.0095 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81114 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "81114", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81114-TN", "81114 TN" ], "locale_variants": {} }, { "sku": "81214-TN", "brand": "SKF", "manufacturer_designation": "81214 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 70, "D_mm": 105, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 146, "static_load_kN": 530, "fatigue_load_limit_kN": 55, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81214 TN as a separable thrust bearing: the 70 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 105 mm housing washer (GS) can be ordered and mounted individually. In 81214 TN, 812 fixes the 105 mm OD and 27 mm height; 14 selects the 70 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 146 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 0.022: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 70 mm bore the minimum load (A 0.022) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 1,300 r/min reference speed is the thermal criterion under load, the 2,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 146/530 kN ratings assume flat, full-support washer seats; a housing face narrower than the 105 mm washer OD invalidates the rating through edge stress.", "Factor A 0.022 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81214 TN need different minimum load and lubrication despite the shared 70×105 mm outline.", "The 146/530 kN ratings and 770 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81214 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81214 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.022 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81214 TN?", "a": "A 81214 TN measures 70 mm bore × 105 mm outside diameter × 27 mm width (2.756 × 4.134 × 1.063 in). From SKF catalogue PUB BU/P1 17000: dynamic C 146 kN, static C0 530 kN, fatigue limit Pu 55 kN, reference speed 1,300 r/min, limiting speed 2,600 r/min, mass about 770 g. Raceway diameters Ea 74 mm / Eb 102 mm and minimum load factor A 0.022 guide the seat design." }, { "q": "How is the 81214 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 14 encodes the 70 mm bore (code 14 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81214", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81214-TN", "81214 TN" ], "locale_variants": {} }, { "sku": "89314-TN", "brand": "SKF", "manufacturer_designation": "89314 TN", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 70, "D_mm": 125, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 186, "static_load_kN": 800, "fatigue_load_limit_kN": 81.5, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 1800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 89314 TN replaces the ball complement with cylindrical rollers: 70 mm bore, 125 mm OD, rated 800 kN static for steady hook and screw loads. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 89314 TN sits in the heavy 893 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.05. Minimum axial load is explicit at factor A 0.05: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.05) is present without clamping the rollers.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 70 mm bore the minimum load (A 0.05) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89314 TN need different minimum load and lubrication despite the shared 70×125 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89314 TN size.", "the 1,300 r/min reference speed is the thermal criterion under load, the 2,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 186/800 kN ratings and 1800 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 89314 TN have?", "a": "A 89314 TN measures 70 mm bore × 125 mm outside diameter × 34 mm width (2.756 × 4.921 × 1.339 in). From SKF catalogue PUB BU/P1 17000: dynamic C 186 kN, static C0 800 kN, fatigue limit Pu 81.5 kN, reference speed 1,300 r/min, limiting speed 2,600 r/min, mass about 1800 g. Raceway diameters Ea 76 mm / Eb 123 mm and minimum load factor A 0.05 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89314 TN belongs to the heavy 893 series, 70×125×34 mm." }, { "q": "Are the washers of 89314 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 89314 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "89314", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89314-TN", "89314 TN" ], "locale_variants": {} }, { "sku": "81115-TN", "brand": "SKF", "manufacturer_designation": "81115 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 75, "D_mm": 100, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 83, "static_load_kN": 335, "fatigue_load_limit_kN": 34, "reference_speed_rpm": 1600, "limiting_speed_rpm": 3200, "max_rpm": 3200, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81115 TN is the rigid-washer thrust solution for a 75 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 83 kN C within just 19 mm of axial space, per the ISO 104 plan. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81115 TN sits in the light 811 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.009. The 390 g mass and 19 mm axial height sit between 75 and 100 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.009) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 75 mm bore the minimum load (A 0.009) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81115 TN size.", "the 1,600 r/min reference speed is the thermal criterion under load, the 3,200 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81115 TN need different minimum load and lubrication despite the shared 75×100 mm outline.", "The 83/335 kN ratings and 390 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 81115 TN have?", "a": "A 81115 TN measures 75 mm bore × 100 mm outside diameter × 19 mm width (2.953 × 3.937 × 0.748 in). From SKF catalogue PUB BU/P1 17000: dynamic C 83 kN, static C0 335 kN, fatigue limit Pu 34 kN, reference speed 1,600 r/min, limiting speed 3,200 r/min, mass about 390 g. Raceway diameters Ea 78 mm / Eb 97 mm and minimum load factor A 0.009 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81115 TN belongs to the light 811 series, 75×100×19 mm." }, { "q": "Are the washers of 81115 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81115 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "81115", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81115-TN", "81115 TN" ], "locale_variants": {} }, { "sku": "81215-TN", "brand": "SKF", "manufacturer_designation": "81215 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 75, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 137, "static_load_kN": 490, "fatigue_load_limit_kN": 50, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81215 TN as a separable thrust bearing: the 75 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 110 mm housing washer (GS) can be ordered and mounted individually. In 81215 TN, 812 fixes the 110 mm OD and 27 mm height; 15 selects the 75 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Speed planning separates the 1,200 r/min thermal reference from the 2,400 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 75 mm bore the minimum load (A 0.019) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Factor A 0.019 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81215 TN need different minimum load and lubrication despite the shared 75×110 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81215 TN size.", "The 137/490 kN ratings and 800 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 890); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Why does 81215 TN need a minimum axial load?", "a": "Below factor A 0.019 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81215 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81215 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.019 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81215 TN?", "a": "A 81215 TN measures 75 mm bore × 110 mm outside diameter × 27 mm width (2.953 × 4.331 × 1.063 in). From SKF catalogue PUB BU/P1 17000: dynamic C 137 kN, static C0 490 kN, fatigue limit Pu 50 kN, reference speed 1,200 r/min, limiting speed 2,400 r/min, mass about 800 g. Raceway diameters Ea 79 mm / Eb 106 mm and minimum load factor A 0.019 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81215", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81215-TN", "81215 TN" ], "locale_variants": {} }, { "sku": "81116-TN", "brand": "SKF", "manufacturer_designation": "81116 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 80, "D_mm": 105, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 81.5, "static_load_kN": 335, "fatigue_load_limit_kN": 34, "reference_speed_rpm": 1500, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 81116 TN denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.009. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81116 TN sits in the light 811 series. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 81.5 kN rating assumes oil or grease reaching the full washer face. The 400 g mass and 19 mm axial height sit between 80 and 105 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Mounting: locate the shaft washer on the 80 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 105 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 80 mm bore the minimum load (A 0.009) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The 81.5/335 kN ratings assume flat, full-support washer seats; a housing face narrower than the 105 mm washer OD invalidates the rating through edge stress.", "Factor A 0.009 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81116 TN need different minimum load and lubrication despite the shared 80×105 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81116 TN size.", "The 81.5/335 kN ratings and 400 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 81116 TN have?", "a": "A 81116 TN measures 80 mm bore × 105 mm outside diameter × 19 mm width (3.15 × 4.134 × 0.748 in). From SKF catalogue PUB BU/P1 17000: dynamic C 81.5 kN, static C0 335 kN, fatigue limit Pu 34 kN, reference speed 1,500 r/min, limiting speed 3,000 r/min, mass about 400 g. Raceway diameters Ea 83 mm / Eb 102 mm and minimum load factor A 0.009 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81116 TN belongs to the light 811 series, 80×105×19 mm." }, { "q": "Are the washers of 81116 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81116 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "81116", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81116-TN", "81116 TN" ], "locale_variants": {} }, { "sku": "81216-TN", "brand": "SKF", "manufacturer_designation": "81216 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 80, "D_mm": 115, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 160, "static_load_kN": 610, "fatigue_load_limit_kN": 63, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81216 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 80×115×28 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81216 TN sits in the heavy 812 series. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 28 mm height. Selection arithmetic: C 160 kN against C0 610 kN gives a C0/C ratio of 3.81 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.03) is present without clamping the rollers.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "grease churning and overheating when a high-speed thrust position is over-packed", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 80 mm bore the minimum load (A 0.03) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81216 TN need different minimum load and lubrication despite the shared 80×115 mm outline.", "Factor A 0.03 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81216 TN size.", "The 160/610 kN ratings and 900 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81216 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81216 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81216 TN in service?", "a": "Unloaded running below factor A 0.03 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,400 r/min limiting." }, { "q": "Which dimensions does the 81216 TN have?", "a": "A 81216 TN measures 80 mm bore × 115 mm outside diameter × 28 mm width (3.15 × 4.528 × 1.102 in). From SKF catalogue PUB BU/P1 17000: dynamic C 160 kN, static C0 610 kN, fatigue limit Pu 63 kN, reference speed 1,200 r/min, limiting speed 2,400 r/min, mass about 900 g. Raceway diameters Ea 84 mm / Eb 112 mm and minimum load factor A 0.03 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81216", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81216-TN", "81216 TN" ], "locale_variants": {} }, { "sku": "89316-TN", "brand": "SKF", "manufacturer_designation": "89316 TN", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 80, "D_mm": 140, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 240, "static_load_kN": 1060, "fatigue_load_limit_kN": 108, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 2350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 89316 TN denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.09. Reading the code: the first three digits 893 give the dimension series (heavy 893 series), the last two 16 encode the 80 mm shaft washer bore (code 16 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Selection arithmetic: C 240 kN against C0 1060 kN gives a C0/C ratio of 4.42 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 80 mm bore the minimum load (A 0.09) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89316 TN size.", "the 1,200 r/min reference speed is the thermal criterion under load, the 2,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 240/1060 kN ratings assume flat, full-support washer seats; a housing face narrower than the 140 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89316 TN need different minimum load and lubrication despite the shared 80×140 mm outline.", "The 240/1060 kN ratings and 2350 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 89316 TN have?", "a": "A 89316 TN measures 80 mm bore × 140 mm outside diameter × 36 mm width (3.15 × 5.512 × 1.417 in). From SKF catalogue PUB BU/P1 17000: dynamic C 240 kN, static C0 1060 kN, fatigue limit Pu 108 kN, reference speed 1,200 r/min, limiting speed 2,400 r/min, mass about 2350 g. Raceway diameters Ea 86 mm / Eb 137 mm and minimum load factor A 0.09 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89316 TN belongs to the heavy 893 series, 80×140×36 mm." }, { "q": "Are the washers of 89316 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 89316 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "89316", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89316-TN", "89316 TN" ], "locale_variants": {} }, { "sku": "89416-M", "brand": "SKF", "manufacturer_designation": "89416 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 80, "D_mm": 170, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 440, "static_load_kN": 1730, "fatigue_load_limit_kN": 173, "reference_speed_rpm": 900, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 7050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 89416 M denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.24. Reading the code: the first three digits 894 give the dimension series (extra-heavy 894 series), the last two 16 encode the 80 mm shaft washer bore (code 16 × 5), and M names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.24. Selection arithmetic: C 440 kN against C0 1730 kN gives a C0/C ratio of 3.93 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Mounting: locate the shaft washer on the 80 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 170 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 80 mm bore the minimum load (A 0.24) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The 440/1730 kN ratings assume flat, full-support washer seats; a housing face narrower than the 170 mm washer OD invalidates the rating through edge stress.", "Factor A 0.24 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89416 M need different minimum load and lubrication despite the shared 80×170 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89416 M size.", "The 440/1730 kN ratings and 7050 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 89416 M have?", "a": "A 89416 M measures 80 mm bore × 170 mm outside diameter × 54 mm width (3.15 × 6.693 × 2.126 in). From SKF catalogue PUB BU/P1 17000: dynamic C 440 kN, static C0 1730 kN, fatigue limit Pu 173 kN, reference speed 900 r/min, limiting speed 1,800 r/min, mass about 7050 g. Raceway diameters Ea 88 mm / Eb 165 mm and minimum load factor A 0.24 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89416 M belongs to the extra-heavy 894 series, 80×170×54 mm." }, { "q": "Are the washers of 89416 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 89416 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "89416", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89416-M", "89416 M" ], "locale_variants": {} }, { "sku": "81117-TN", "brand": "SKF", "manufacturer_designation": "81117 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 85, "D_mm": 110, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 88, "static_load_kN": 365, "fatigue_load_limit_kN": 37.5, "reference_speed_rpm": 1500, "limiting_speed_rpm": 3000, "max_rpm": 3000, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81117 TN carries pure axial load at low to moderate speed: 88 kN dynamic and 365 kN static across a 85×110 mm washer pair, 19 mm overall height. The designation 81117 TN states 811 series, 85 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Minimum axial load is explicit at factor A 0.011: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 85 mm bore the minimum load (A 0.011) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Factor A 0.011 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81117 TN size.", "the 1,500 r/min reference speed is the thermal criterion under load, the 3,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 88/365 kN ratings and 420 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 81117 TN?", "a": "A 81117 TN measures 85 mm bore × 110 mm outside diameter × 19 mm width (3.346 × 4.331 × 0.748 in). From SKF catalogue PUB BU/P1 17000: dynamic C 88 kN, static C0 365 kN, fatigue limit Pu 37.5 kN, reference speed 1,500 r/min, limiting speed 3,000 r/min, mass about 420 g. Raceway diameters Ea 87 mm / Eb 108 mm and minimum load factor A 0.011 guide the seat design." }, { "q": "How is the 81117 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 17 encodes the 85 mm bore (code 17 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81117 TN need a minimum axial load?", "a": "Below factor A 0.011 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81117 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "81117", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81117-TN", "81117 TN" ], "locale_variants": {} }, { "sku": "81217-TN", "brand": "SKF", "manufacturer_designation": "81217 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 85, "D_mm": 125, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 170, "static_load_kN": 640, "fatigue_load_limit_kN": 67, "reference_speed_rpm": 1100, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81217 TN replaces the ball complement with cylindrical rollers: 85 mm bore, 125 mm OD, rated 640 kN static for steady hook and screw loads. The designation 81217 TN states 812 series, 85 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.033. One direction only: 81217 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Mounting: locate the shaft washer on the 85 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 125 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 85 mm bore the minimum load (A 0.033) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81217 TN need different minimum load and lubrication despite the shared 85×125 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81217 TN size.", "the 1,100 r/min reference speed is the thermal criterion under load, the 2,200 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 170/640 kN ratings assume flat, full-support washer seats; a housing face narrower than the 125 mm washer OD invalidates the rating through edge stress.", "The 170/640 kN ratings and 1200 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Why does 81217 TN need a minimum axial load?", "a": "Below factor A 0.033 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81217 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81217 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.033 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81217 TN?", "a": "A 81217 TN measures 85 mm bore × 125 mm outside diameter × 31 mm width (3.346 × 4.921 × 1.22 in). From SKF catalogue PUB BU/P1 17000: dynamic C 170 kN, static C0 640 kN, fatigue limit Pu 67 kN, reference speed 1,100 r/min, limiting speed 2,200 r/min, mass about 1200 g. Raceway diameters Ea 90 mm / Eb 119 mm and minimum load factor A 0.033 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81217", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81217-TN", "81217 TN" ], "locale_variants": {} }, { "sku": "81118-TN", "brand": "SKF", "manufacturer_designation": "81118 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 90, "D_mm": 120, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 110, "static_load_kN": 450, "fatigue_load_limit_kN": 45.5, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2600, "max_rpm": 2600, "weight_g": 620, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81118 TN carries pure axial load at low to moderate speed: 110 kN dynamic and 450 kN static across a 90×120 mm washer pair, 22 mm overall height. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 18 encode the 90 mm shaft washer bore (code 18 × 5), and TN names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.016. Speed planning separates the 1,300 r/min thermal reference from the 2,600 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 90 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 120 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 90 mm bore the minimum load (A 0.016) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81118 TN need different minimum load and lubrication despite the shared 90×120 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81118 TN size.", "the 1,300 r/min reference speed is the thermal criterion under load, the 2,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 110/450 kN ratings and 620 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 81118 TN have?", "a": "A 81118 TN measures 90 mm bore × 120 mm outside diameter × 22 mm width (3.543 × 4.724 × 0.866 in). From SKF catalogue PUB BU/P1 17000: dynamic C 110 kN, static C0 450 kN, fatigue limit Pu 45.5 kN, reference speed 1,300 r/min, limiting speed 2,600 r/min, mass about 620 g. Raceway diameters Ea 93 mm / Eb 117 mm and minimum load factor A 0.016 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81118 TN belongs to the light 811 series, 90×120×22 mm." }, { "q": "Are the washers of 81118 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81118 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "81118", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81118-TN", "81118 TN" ], "locale_variants": {} }, { "sku": "81218-TN", "brand": "SKF", "manufacturer_designation": "81218 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 90, "D_mm": 135, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 232, "static_load_kN": 865, "fatigue_load_limit_kN": 90, "reference_speed_rpm": 1000, "limiting_speed_rpm": 2000, "max_rpm": 2000, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81218 TN replaces the ball complement with cylindrical rollers: 90 mm bore, 135 mm OD, rated 865 kN static for steady hook and screw loads. The designation 81218 TN states 812 series, 90 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. One direction only: 81218 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.06) is present without clamping the rollers.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 90 mm bore the minimum load (A 0.06) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 1,000 r/min reference speed is the thermal criterion under load, the 2,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 232/865 kN ratings assume flat, full-support washer seats; a housing face narrower than the 135 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81218 TN need different minimum load and lubrication despite the shared 90×135 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81218 TN size.", "The 232/865 kN ratings and 1750 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Why does 81218 TN need a minimum axial load?", "a": "Below factor A 0.06 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81218 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81218 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.06 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81218 TN?", "a": "A 81218 TN measures 90 mm bore × 135 mm outside diameter × 35 mm width (3.543 × 5.315 × 1.378 in). From SKF catalogue PUB BU/P1 17000: dynamic C 232 kN, static C0 865 kN, fatigue limit Pu 90 kN, reference speed 1,000 r/min, limiting speed 2,000 r/min, mass about 1750 g. Raceway diameters Ea 95 mm / Eb 129 mm and minimum load factor A 0.06 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81218", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81218-TN", "81218 TN" ], "locale_variants": {} }, { "sku": "81120-TN", "brand": "SKF", "manufacturer_designation": "81120 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 100, "D_mm": 135, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 156, "static_load_kN": 630, "fatigue_load_limit_kN": 62, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2400, "max_rpm": 2400, "weight_g": 950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81120 TN replaces the ball complement with cylindrical rollers: 100 mm bore, 135 mm OD, rated 630 kN static for steady hook and screw loads. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81120 TN sits in the light 811 series. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 25 mm height. One direction only: 81120 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.032) is present without clamping the rollers.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 100 mm bore the minimum load (A 0.032) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81120 TN need different minimum load and lubrication despite the shared 100×135 mm outline.", "The 156/630 kN ratings assume flat, full-support washer seats; a housing face narrower than the 135 mm washer OD invalidates the rating through edge stress.", "Factor A 0.032 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The 156/630 kN ratings and 950 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81120 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81120 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81120 TN in service?", "a": "Unloaded running below factor A 0.032 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,400 r/min limiting." }, { "q": "Which dimensions does the 81120 TN have?", "a": "A 81120 TN measures 100 mm bore × 135 mm outside diameter × 25 mm width (3.937 × 5.315 × 0.984 in). From SKF catalogue PUB BU/P1 17000: dynamic C 156 kN, static C0 630 kN, fatigue limit Pu 62 kN, reference speed 1,200 r/min, limiting speed 2,400 r/min, mass about 950 g. Raceway diameters Ea 104 mm / Eb 131 mm and minimum load factor A 0.032 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81120", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81120-TN", "81120 TN" ], "locale_variants": {} }, { "sku": "81220-TN", "brand": "SKF", "manufacturer_designation": "81220 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 100, "D_mm": 150, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 270, "static_load_kN": 1060, "fatigue_load_limit_kN": 104, "reference_speed_rpm": 900, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The heavy 812 series bearing 81220 TN carries pure axial load at low to moderate speed: 270 kN dynamic and 1060 kN static across a 100×150 mm washer pair, 38 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81220 TN sits in the heavy 812 series. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 270 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 0.09: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 100 mm bore the minimum load (A 0.09) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81220 TN size.", "the 900 r/min reference speed is the thermal criterion under load, the 1,800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Factor A 0.09 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 270/1060 kN ratings and 2200 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81220 TN in service?", "a": "Unloaded running below factor A 0.09 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,800 r/min limiting." }, { "q": "Which dimensions does the 81220 TN have?", "a": "A 81220 TN measures 100 mm bore × 150 mm outside diameter × 38 mm width (3.937 × 5.906 × 1.496 in). From SKF catalogue PUB BU/P1 17000: dynamic C 270 kN, static C0 1060 kN, fatigue limit Pu 104 kN, reference speed 900 r/min, limiting speed 1,800 r/min, mass about 2200 g. Raceway diameters Ea 107 mm / Eb 142 mm and minimum load factor A 0.09 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81220 TN belongs to the heavy 812 series, 100×150×38 mm." }, { "q": "Are the washers of 81220 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81220", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81220-TN", "81220 TN" ], "locale_variants": {} }, { "sku": "89320-M", "brand": "SKF", "manufacturer_designation": "89320 M", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 100, "D_mm": 170, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 300, "static_load_kN": 1370, "fatigue_load_limit_kN": 132, "reference_speed_rpm": 950, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 4550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 89320 M replaces the ball complement with cylindrical rollers: 100 mm bore, 170 mm OD, rated 1370 kN static for steady hook and screw loads. In 89320 M, 893 fixes the 170 mm OD and 42 mm height; 20 selects the 100 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 300 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 0.15: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.15) is present without clamping the rollers.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 100 mm bore the minimum load (A 0.15) is still small, but a vertical shaft at rest loses it entirely — specify springs or check the rotor weight exceeds F_am at zero speed.", "the 950 r/min reference speed is the thermal criterion under load, the 1,900 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 300/1370 kN ratings assume flat, full-support washer seats; a housing face narrower than the 170 mm washer OD invalidates the rating through edge stress.", "Factor A 0.15 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89320 M need different minimum load and lubrication despite the shared 100×170 mm outline.", "The 300/1370 kN ratings and 4550 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Why does 89320 M need a minimum axial load?", "a": "Below factor A 0.15 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 89320 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 89320 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.15 minimum load is present." }, { "q": "What are the dimensions and ratings of the 89320 M?", "a": "A 89320 M measures 100 mm bore × 170 mm outside diameter × 42 mm width (3.937 × 6.693 × 1.654 in). From SKF catalogue PUB BU/P1 17000: dynamic C 300 kN, static C0 1370 kN, fatigue limit Pu 132 kN, reference speed 950 r/min, limiting speed 1,900 r/min, mass about 4550 g. Raceway diameters Ea 109 mm / Eb 166 mm and minimum load factor A 0.15 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "89320", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89320-M", "89320 M" ], "locale_variants": {} }, { "sku": "81122-TN", "brand": "SKF", "manufacturer_designation": "81122 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 110, "D_mm": 145, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 163, "static_load_kN": 680, "fatigue_load_limit_kN": 65.5, "reference_speed_rpm": 1100, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81122 TN is the rigid-washer thrust solution for a 110 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 163 kN C within just 25 mm of axial space, per the ISO 104 plan. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 22 encode the 110 mm shaft washer bore (code 22 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. The 1050 g mass and 25 mm axial height sit between 110 and 145 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.037) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 110 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 25 mm.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81122 TN size.", "the 1,100 r/min reference speed is the thermal criterion under load, the 2,200 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81122 TN need different minimum load and lubrication despite the shared 110×145 mm outline.", "The 163/680 kN ratings and 1050 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81122 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81122 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81122 TN in service?", "a": "Unloaded running below factor A 0.037 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 2,200 r/min limiting." }, { "q": "Which dimensions does the 81122 TN have?", "a": "A 81122 TN measures 110 mm bore × 145 mm outside diameter × 25 mm width (4.331 × 5.709 × 0.984 in). From SKF catalogue PUB BU/P1 17000: dynamic C 163 kN, static C0 680 kN, fatigue limit Pu 65.5 kN, reference speed 1,100 r/min, limiting speed 2,200 r/min, mass about 1050 g. Raceway diameters Ea 114 mm / Eb 141 mm and minimum load factor A 0.037 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81122", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81122-TN", "81122 TN" ], "locale_variants": {} }, { "sku": "81222-TN", "brand": "SKF", "manufacturer_designation": "81222 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 110, "D_mm": 160, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 260, "static_load_kN": 1000, "fatigue_load_limit_kN": 98, "reference_speed_rpm": 850, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81222 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 110×160×38 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. The designation 81222 TN states 812 series, 110 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 38 mm height. Speed planning separates the 850 r/min thermal reference from the 1,700 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Mounting: locate the shaft washer on the 110 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 160 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 110 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 38 mm.", "Factor A 0.08 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81222 TN need different minimum load and lubrication despite the shared 110×160 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81222 TN size.", "The 260/1000 kN ratings and 2300 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81222 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.08 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81222 TN?", "a": "A 81222 TN measures 110 mm bore × 160 mm outside diameter × 38 mm width (4.331 × 6.299 × 1.496 in). From SKF catalogue PUB BU/P1 17000: dynamic C 260 kN, static C0 1000 kN, fatigue limit Pu 98 kN, reference speed 850 r/min, limiting speed 1,700 r/min, mass about 2300 g. Raceway diameters Ea 117 mm / Eb 152 mm and minimum load factor A 0.08 guide the seat design." }, { "q": "How is the 81222 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 22 encodes the 110 mm bore (code 22 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81222 TN need a minimum axial load?", "a": "Below factor A 0.08 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81222", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81222-TN", "81222 TN" ], "locale_variants": {} }, { "sku": "89322-M", "brand": "SKF", "manufacturer_designation": "89322 M", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 110, "D_mm": 190, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 400, "static_load_kN": 1830, "fatigue_load_limit_kN": 173, "reference_speed_rpm": 850, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 6700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 89322 M replaces the ball complement with cylindrical rollers: 110 mm bore, 190 mm OD, rated 1830 kN static for steady hook and screw loads. Reading the code: the first three digits 893 give the dimension series (heavy 893 series), the last two 22 encode the 110 mm shaft washer bore (code 22 × 5), and M names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.27. Selection arithmetic: C 400 kN against C0 1830 kN gives a C0/C ratio of 4.58 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 110 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 48 mm.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89322 M need different minimum load and lubrication despite the shared 110×190 mm outline.", "Factor A 0.27 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89322 M size.", "The 400/1830 kN ratings and 6700 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 89322 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 89322 M in service?", "a": "Unloaded running below factor A 0.27 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,700 r/min limiting." }, { "q": "Which dimensions does the 89322 M have?", "a": "A 89322 M measures 110 mm bore × 190 mm outside diameter × 48 mm width (4.331 × 7.48 × 1.89 in). From SKF catalogue PUB BU/P1 17000: dynamic C 400 kN, static C0 1830 kN, fatigue limit Pu 173 kN, reference speed 850 r/min, limiting speed 1,700 r/min, mass about 6700 g. Raceway diameters Ea 120 mm / Eb 185 mm and minimum load factor A 0.27 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89322 M belongs to the heavy 893 series, 110×190×48 mm." } ], "cross_ref": [ { "equiv_sku": "89322", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89322-M", "89322 M" ], "locale_variants": {} }, { "sku": "81124-TN", "brand": "SKF", "manufacturer_designation": "81124 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 120, "D_mm": 155, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 170, "static_load_kN": 735, "fatigue_load_limit_kN": 68, "reference_speed_rpm": 1100, "limiting_speed_rpm": 2200, "max_rpm": 2200, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81124 TN carries pure axial load at low to moderate speed: 170 kN dynamic and 735 kN static across a 120×155 mm washer pair, 25 mm overall height. In 81124 TN, 811 fixes the 155 mm OD and 25 mm height; 24 selects the 120 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 25 mm height. Speed planning separates the 1,100 r/min thermal reference from the 2,200 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.043) is present without clamping the rollers.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 120 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 25 mm.", "Factor A 0.043 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81124 TN need different minimum load and lubrication despite the shared 120×155 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81124 TN size.", "The 170/735 kN ratings and 1100 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81124 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 24 encodes the 120 mm bore (code 24 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81124 TN need a minimum axial load?", "a": "Below factor A 0.043 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81124 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81124 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.043 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81124", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81124-TN", "81124 TN" ], "locale_variants": {} }, { "sku": "81224-TN", "brand": "SKF", "manufacturer_designation": "81224 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 120, "D_mm": 170, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 255, "static_load_kN": 1000, "fatigue_load_limit_kN": 96.5, "reference_speed_rpm": 800, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81224 TN replaces the ball complement with cylindrical rollers: 120 mm bore, 170 mm OD, rated 1000 kN static for steady hook and screw loads. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 24 encode the 120 mm shaft washer bore (code 24 × 5), and TN names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Selection arithmetic: C 255 kN against C0 1000 kN gives a C0/C ratio of 3.92 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Mounting: locate the shaft washer on the 120 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 170 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "hard-particle indentation where oil or grease filtration is inadequate", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 120 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 39 mm.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81224 TN size.", "the 800 r/min reference speed is the thermal criterion under load, the 1,600 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 255/1000 kN ratings assume flat, full-support washer seats; a housing face narrower than the 170 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81224 TN need different minimum load and lubrication despite the shared 120×170 mm outline.", "The 255/1000 kN ratings and 2550 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81224 TN in service?", "a": "Unloaded running below factor A 0.08 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,600 r/min limiting." }, { "q": "Which dimensions does the 81224 TN have?", "a": "A 81224 TN measures 120 mm bore × 170 mm outside diameter × 39 mm width (4.724 × 6.693 × 1.535 in). From SKF catalogue PUB BU/P1 17000: dynamic C 255 kN, static C0 1000 kN, fatigue limit Pu 96.5 kN, reference speed 800 r/min, limiting speed 1,600 r/min, mass about 2550 g. Raceway diameters Ea 127 mm / Eb 162 mm and minimum load factor A 0.08 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81224 TN belongs to the heavy 812 series, 120×170×39 mm." }, { "q": "Are the washers of 81224 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81224", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81224-TN", "81224 TN" ], "locale_variants": {} }, { "sku": "89324-M", "brand": "SKF", "manufacturer_designation": "89324 M", "series": "89300-series", "type": "cylindrical_roller_thrust", "d_mm": 120, "D_mm": 210, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 510, "static_load_kN": 2360, "fatigue_load_limit_kN": 216, "reference_speed_rpm": 750, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 9450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "89324 M is the rigid-washer thrust solution for a 120 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 510 kN C within just 54 mm of axial space, per the ISO 104 plan. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 89324 M sits in the heavy 893 series. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 510 kN rating assumes oil or grease reaching the full washer face. Static safety matters for shock duty: compare peak axial force against C0 2360 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: locate the shaft washer on the 120 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 210 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 120 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 54 mm.", "The 510/2360 kN ratings assume flat, full-support washer seats; a housing face narrower than the 210 mm washer OD invalidates the rating through edge stress.", "Factor A 0.45 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89324 M need different minimum load and lubrication despite the shared 120×210 mm outline.", "The 510/2360 kN ratings and 9450 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 89324 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 89324 M in service?", "a": "Unloaded running below factor A 0.45 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,500 r/min limiting." }, { "q": "Which dimensions does the 89324 M have?", "a": "A 89324 M measures 120 mm bore × 210 mm outside diameter × 54 mm width (4.724 × 8.268 × 2.126 in). From SKF catalogue PUB BU/P1 17000: dynamic C 510 kN, static C0 2360 kN, fatigue limit Pu 216 kN, reference speed 750 r/min, limiting speed 1,500 r/min, mass about 9450 g. Raceway diameters Ea 132 mm / Eb 205 mm and minimum load factor A 0.45 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89324 M belongs to the heavy 893 series, 120×210×54 mm." } ], "cross_ref": [ { "equiv_sku": "89324", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89324-M", "89324 M" ], "locale_variants": {} }, { "sku": "81126-TN", "brand": "SKF", "manufacturer_designation": "81126 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 130, "D_mm": 170, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 200, "static_load_kN": 880, "fatigue_load_limit_kN": 81.5, "reference_speed_rpm": 950, "limiting_speed_rpm": 1900, "max_rpm": 1900, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81126 TN as a separable thrust bearing: the 130 mm shaft washer (WS), the glass fibre reinforced PA66 TN cage holding short cylindrical rollers, and the 170 mm housing washer (GS) can be ordered and mounted individually. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81126 TN sits in the light 811 series. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the glass fibre reinforced PA66 TN cage is standard for this size. Selection arithmetic: C 200 kN against C0 880 kN gives a C0/C ratio of 4.40 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.062) is present without clamping the rollers.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 130 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 30 mm.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81126 TN size.", "the 950 r/min reference speed is the thermal criterion under load, the 1,900 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 200/880 kN ratings assume flat, full-support washer seats; a housing face narrower than the 170 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81126 TN need different minimum load and lubrication despite the shared 130×170 mm outline.", "The 200/880 kN ratings and 1650 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81126 TN belongs to the light 811 series, 130×170×30 mm." }, { "q": "Are the washers of 81126 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81126 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81126 TN in service?", "a": "Unloaded running below factor A 0.062 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,900 r/min limiting." } ], "cross_ref": [ { "equiv_sku": "81126", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81126-TN", "81126 TN" ], "locale_variants": {} }, { "sku": "81226-TN", "brand": "SKF", "manufacturer_designation": "81226 TN", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 130, "D_mm": 190, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 380, "static_load_kN": 1460, "fatigue_load_limit_kN": 137, "reference_speed_rpm": 700, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81226 TN is the rigid-washer thrust solution for a 130 mm shaft: unlike ball thrust types, the line contact of cylindrical rollers gives 380 kN C within just 45 mm of axial space, per the ISO 104 plan. In 81226 TN, 812 fixes the 190 mm OD and 45 mm height; 26 selects the 130 mm seat, and the glass fibre reinforced PA66 TN cage is the only execution suffix on these rigid-washer bearings. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.17. Static safety matters for shock duty: compare peak axial force against C0 1460 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "false brinelling and rust-red witness marks on standby machines under external vibration", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 130 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 45 mm.", "Factor A 0.17 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 380/1460 kN ratings assume flat, full-support washer seats; a housing face narrower than the 190 mm washer OD invalidates the rating through edge stress.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81226 TN need different minimum load and lubrication despite the shared 130×190 mm outline.", "The 380/1460 kN ratings and 4000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81226 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81226 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.17 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81226 TN?", "a": "A 81226 TN measures 130 mm bore × 190 mm outside diameter × 45 mm width (5.118 × 7.48 × 1.772 in). From SKF catalogue PUB BU/P1 17000: dynamic C 380 kN, static C0 1460 kN, fatigue limit Pu 137 kN, reference speed 700 r/min, limiting speed 1,400 r/min, mass about 4000 g. Raceway diameters Ea 137 mm / Eb 181 mm and minimum load factor A 0.17 guide the seat design." }, { "q": "How is the 81226 TN designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 26 encodes the 130 mm bore (code 26 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81226", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81226-TN", "81226 TN" ], "locale_variants": {} }, { "sku": "81128-TN", "brand": "SKF", "manufacturer_designation": "81128 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 140, "D_mm": 180, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 208, "static_load_kN": 930, "fatigue_load_limit_kN": 85, "reference_speed_rpm": 900, "limiting_speed_rpm": 1800, "max_rpm": 1800, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81128 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 140×180×31 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. The designation 81128 TN states 811 series, 140 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 208 kN rating assumes oil or grease reaching the full washer face. One direction only: 81128 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.069) is present without clamping the rollers.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "grease churning and overheating when a high-speed thrust position is over-packed", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 140 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 31 mm.", "Factor A 0.069 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81128 TN need different minimum load and lubrication despite the shared 140×180 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81128 TN size.", "The 208/930 kN ratings and 1900 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How is the 81128 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 28 encodes the 140 mm bore (code 28 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81128 TN need a minimum axial load?", "a": "Below factor A 0.069 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81128 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81128 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.069 minimum load is present." } ], "cross_ref": [ { "equiv_sku": "81128", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81128-TN", "81128 TN" ], "locale_variants": {} }, { "sku": "81228-M", "brand": "SKF", "manufacturer_designation": "81228 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 140, "D_mm": 200, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 360, "static_load_kN": 1400, "fatigue_load_limit_kN": 129, "reference_speed_rpm": 700, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 5050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81228 M as a separable thrust bearing: the 140 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 200 mm housing washer (GS) can be ordered and mounted individually. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 28 encode the 140 mm shaft washer bore (code 28 × 5), and M names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.16. Minimum axial load is explicit at factor A 0.16: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.16) is present without clamping the rollers.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 140 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 46 mm.", "The 360/1400 kN ratings assume flat, full-support washer seats; a housing face narrower than the 200 mm washer OD invalidates the rating through edge stress.", "Factor A 0.16 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "the 700 r/min reference speed is the thermal criterion under load, the 1,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81228 M need different minimum load and lubrication despite the shared 140×200 mm outline.", "The 360/1400 kN ratings and 5050 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 81228 M have?", "a": "A 81228 M measures 140 mm bore × 200 mm outside diameter × 46 mm width (5.512 × 7.874 × 1.811 in). From SKF catalogue PUB BU/P1 17000: dynamic C 360 kN, static C0 1400 kN, fatigue limit Pu 129 kN, reference speed 700 r/min, limiting speed 1,400 r/min, mass about 5050 g. Raceway diameters Ea 150 mm / Eb 191 mm and minimum load factor A 0.16 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81228 M belongs to the heavy 812 series, 140×200×46 mm." }, { "q": "Are the washers of 81228 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81228 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "81228", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81228-M", "81228 M" ], "locale_variants": {} }, { "sku": "81130-TN", "brand": "SKF", "manufacturer_designation": "81130 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 150, "D_mm": 190, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 212, "static_load_kN": 1000, "fatigue_load_limit_kN": 88, "reference_speed_rpm": 850, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 2200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, 81130 TN denotes a cylindrical roller thrust bearing whose rollers run flat on hardened, ground washers — no radial capacity, one axial direction only, and a minimum axial load of factor A 0.08. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81130 TN sits in the light 811 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.08. Minimum axial load is explicit at factor A 0.08: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "condensation pitting in machines that run intermittently in humid environments", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 150 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 31 mm.", "The 212/1000 kN ratings assume flat, full-support washer seats; a housing face narrower than the 190 mm washer OD invalidates the rating through edge stress.", "Factor A 0.08 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "the 850 r/min reference speed is the thermal criterion under load, the 1,700 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81130 TN need different minimum load and lubrication despite the shared 150×190 mm outline.", "The 212/1000 kN ratings and 2200 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81130 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81130 TN in service?", "a": "Unloaded running below factor A 0.08 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,700 r/min limiting." }, { "q": "Which dimensions does the 81130 TN have?", "a": "A 81130 TN measures 150 mm bore × 190 mm outside diameter × 31 mm width (5.906 × 7.48 × 1.22 in). From SKF catalogue PUB BU/P1 17000: dynamic C 212 kN, static C0 1000 kN, fatigue limit Pu 88 kN, reference speed 850 r/min, limiting speed 1,700 r/min, mass about 2200 g. Raceway diameters Ea 155 mm / Eb 185 mm and minimum load factor A 0.08 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81130 TN belongs to the light 811 series, 150×190×31 mm." } ], "cross_ref": [ { "equiv_sku": "81130", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81130-TN", "81130 TN" ], "locale_variants": {} }, { "sku": "81230-M", "brand": "SKF", "manufacturer_designation": "81230 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 150, "D_mm": 215, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 465, "static_load_kN": 1900, "fatigue_load_limit_kN": 170, "reference_speed_rpm": 630, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 7200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81230 M as a separable thrust bearing: the 150 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 215 mm housing washer (GS) can be ordered and mounted individually. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81230 M sits in the heavy 812 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.29. Static safety matters for shock duty: compare peak axial force against C0 1900 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: locate the shaft washer on the 150 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 215 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 150 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 50 mm.", "The 465/1900 kN ratings assume flat, full-support washer seats; a housing face narrower than the 215 mm washer OD invalidates the rating through edge stress.", "Factor A 0.29 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81230 M need different minimum load and lubrication despite the shared 150×215 mm outline.", "The 465/1900 kN ratings and 7200 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81230 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81230 M in service?", "a": "Unloaded running below factor A 0.29 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,300 r/min limiting." }, { "q": "Which dimensions does the 81230 M have?", "a": "A 81230 M measures 150 mm bore × 215 mm outside diameter × 50 mm width (5.906 × 8.465 × 1.969 in). From SKF catalogue PUB BU/P1 17000: dynamic C 465 kN, static C0 1900 kN, fatigue limit Pu 170 kN, reference speed 630 r/min, limiting speed 1,300 r/min, mass about 7200 g. Raceway diameters Ea 162 mm / Eb 210 mm and minimum load factor A 0.29 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81230 M belongs to the heavy 812 series, 150×215×50 mm." } ], "cross_ref": [ { "equiv_sku": "81230", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81230-M", "81230 M" ], "locale_variants": {} }, { "sku": "81132-TN", "brand": "SKF", "manufacturer_designation": "81132 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 160, "D_mm": 200, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 216, "static_load_kN": 1020, "fatigue_load_limit_kN": 90, "reference_speed_rpm": 850, "limiting_speed_rpm": 1700, "max_rpm": 1700, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81132 TN carries pure axial load at low to moderate speed: 216 kN dynamic and 1020 kN static across a 160×200 mm washer pair, 31 mm overall height. The designation 81132 TN states 811 series, 160 mm bore, glass fibre reinforced PA66 TN cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 31 mm height. Speed planning separates the 850 r/min thermal reference from the 1,700 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 160 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 31 mm.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81132 TN need different minimum load and lubrication despite the shared 160×200 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81132 TN size.", "Factor A 0.083 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 216/1020 kN ratings and 2100 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81132 TN take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81132 TN be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.083 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81132 TN?", "a": "A 81132 TN measures 160 mm bore × 200 mm outside diameter × 31 mm width (6.299 × 7.874 × 1.22 in). From SKF catalogue PUB BU/P1 17000: dynamic C 216 kN, static C0 1020 kN, fatigue limit Pu 90 kN, reference speed 850 r/min, limiting speed 1,700 r/min, mass about 2100 g. Raceway diameters Ea 165 mm / Eb 195 mm and minimum load factor A 0.083 guide the seat design." }, { "q": "How is the 81132 TN designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 32 encodes the 160 mm bore (code 32 × 5); the suffix denotes the glass fibre reinforced PA66 TN cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81132", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81132-TN", "81132 TN" ], "locale_variants": {} }, { "sku": "81232-M", "brand": "SKF", "manufacturer_designation": "81232 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 160, "D_mm": 225, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 480, "static_load_kN": 2000, "fatigue_load_limit_kN": 176, "reference_speed_rpm": 600, "limiting_speed_rpm": 1200, "max_rpm": 1200, "weight_g": 7600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81232 M as a separable thrust bearing: the 160 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 225 mm housing washer (GS) can be ordered and mounted individually. In 81232 M, 812 fixes the 225 mm OD and 51 mm height; 32 selects the 160 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 51 mm height. Minimum axial load is explicit at factor A 0.32: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.32) is present without clamping the rollers.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 160 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 51 mm.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81232 M need different minimum load and lubrication despite the shared 160×225 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81232 M size.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "the 600 r/min reference speed is the thermal criterion under load, the 1,200 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 480/2000 kN ratings and 7600 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81232 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.32 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81232 M?", "a": "A 81232 M measures 160 mm bore × 225 mm outside diameter × 51 mm width (6.299 × 8.858 × 2.008 in). From SKF catalogue PUB BU/P1 17000: dynamic C 480 kN, static C0 2000 kN, fatigue limit Pu 176 kN, reference speed 600 r/min, limiting speed 1,200 r/min, mass about 7600 g. Raceway diameters Ea 171 mm / Eb 219 mm and minimum load factor A 0.32 guide the seat design." }, { "q": "How is the 81232 M designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 32 encodes the 160 mm bore (code 32 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81232 M need a minimum axial load?", "a": "Below factor A 0.32 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81232", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81232-M", "81232 M" ], "locale_variants": {} }, { "sku": "89432-M", "brand": "SKF", "manufacturer_designation": "89432 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 160, "D_mm": 320, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1430, "static_load_kN": 6400, "fatigue_load_limit_kN": 540, "reference_speed_rpm": 480, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 42000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The extra-heavy 894 series bearing 89432 M carries pure axial load at low to moderate speed: 1430 kN dynamic and 6400 kN static across a 160×320 mm washer pair, 95 mm overall height. Reading the code: the first three digits 894 give the dimension series (extra-heavy 894 series), the last two 32 encode the 160 mm shaft washer bore (code 32 × 5), and M names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. The 42000 g mass and 95 mm axial height sit between 160 and 320 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 160 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 95 mm.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89432 M need different minimum load and lubrication despite the shared 160×320 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89432 M size.", "the 480 r/min reference speed is the thermal criterion under load, the 950 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 1430/6400 kN ratings and 42000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 89432 M in service?", "a": "Unloaded running below factor A 3.3 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 950 r/min limiting." }, { "q": "Which dimensions does the 89432 M have?", "a": "A 89432 M measures 160 mm bore × 320 mm outside diameter × 95 mm width (6.299 × 12.598 × 3.74 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1430 kN, static C0 6400 kN, fatigue limit Pu 540 kN, reference speed 480 r/min, limiting speed 950 r/min, mass about 42000 g. Raceway diameters Ea 179 mm / Eb 313 mm and minimum load factor A 3.3 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89432 M belongs to the extra-heavy 894 series, 160×320×95 mm." }, { "q": "Are the washers of 89432 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "89432", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89432-M", "89432 M" ], "locale_variants": {} }, { "sku": "81134-TN", "brand": "SKF", "manufacturer_designation": "81134 TN", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 170, "D_mm": 215, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 285, "static_load_kN": 1340, "fatigue_load_limit_kN": 118, "reference_speed_rpm": 800, "limiting_speed_rpm": 1600, "max_rpm": 1600, "weight_g": 2400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81134 TN is a single-direction cylindrical roller thrust bearing to ISO 104 in the light 811 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 170×215×34 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 34 encode the 170 mm shaft washer bore (code 34 × 5), and TN names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.14. One direction only: 81134 TN cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "false brinelling and rust-red witness marks on standby machines under external vibration", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 170 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 34 mm.", "The 285/1340 kN ratings assume flat, full-support washer seats; a housing face narrower than the 215 mm washer OD invalidates the rating through edge stress.", "Factor A 0.14 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the glass fibre reinforced PA66 TN cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81134 TN need different minimum load and lubrication despite the shared 170×215 mm outline.", "The 285/1340 kN ratings and 2400 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81134 TN separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81134 TN?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81134 TN in service?", "a": "Unloaded running below factor A 0.14 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,600 r/min limiting." }, { "q": "Which dimensions does the 81134 TN have?", "a": "A 81134 TN measures 170 mm bore × 215 mm outside diameter × 34 mm width (6.693 × 8.465 × 1.339 in). From SKF catalogue PUB BU/P1 17000: dynamic C 285 kN, static C0 1340 kN, fatigue limit Pu 118 kN, reference speed 800 r/min, limiting speed 1,600 r/min, mass about 2400 g. Raceway diameters Ea 176 mm / Eb 209 mm and minimum load factor A 0.14 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81134", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81134-TN", "81134 TN" ], "locale_variants": {} }, { "sku": "81234-M", "brand": "SKF", "manufacturer_designation": "81234 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 170, "D_mm": 240, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 540, "static_load_kN": 2280, "fatigue_load_limit_kN": 200, "reference_speed_rpm": 560, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 9300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81234 M as a separable thrust bearing: the 170 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 240 mm housing washer (GS) can be ordered and mounted individually. The designation 81234 M states 812 series, 170 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 540 kN rating assumes oil or grease reaching the full washer face. Selection arithmetic: C 540 kN against C0 2280 kN gives a C0/C ratio of 4.22 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.42) is present without clamping the rollers.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 170 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 55 mm.", "Factor A 0.42 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81234 M need different minimum load and lubrication despite the shared 170×240 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81234 M size.", "The 540/2280 kN ratings and 9300 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81234 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.42 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81234 M?", "a": "A 81234 M measures 170 mm bore × 240 mm outside diameter × 55 mm width (6.693 × 9.449 × 2.165 in). From SKF catalogue PUB BU/P1 17000: dynamic C 540 kN, static C0 2280 kN, fatigue limit Pu 200 kN, reference speed 560 r/min, limiting speed 1,100 r/min, mass about 9300 g. Raceway diameters Ea 184 mm / Eb 233 mm and minimum load factor A 0.42 guide the seat design." }, { "q": "How is the 81234 M designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 34 encodes the 170 mm bore (code 34 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81234 M need a minimum axial load?", "a": "Below factor A 0.42 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81234", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81234-M", "81234 M" ], "locale_variants": {} }, { "sku": "89434-M", "brand": "SKF", "manufacturer_designation": "89434 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 170, "D_mm": 340, "B_mm": 103, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1600, "static_load_kN": 7200, "fatigue_load_limit_kN": 600, "reference_speed_rpm": 430, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 52000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The extra-heavy 894 series bearing 89434 M carries pure axial load at low to moderate speed: 1600 kN dynamic and 7200 kN static across a 170×340 mm washer pair, 103 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 89434 M sits in the extra-heavy 894 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 4.15. Speed planning separates the 430 r/min thermal reference from the 850 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 170 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 103 mm.", "The 1600/7200 kN ratings assume flat, full-support washer seats; a housing face narrower than the 340 mm washer OD invalidates the rating through edge stress.", "Factor A 4.15 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89434 M size.", "the 430 r/min reference speed is the thermal criterion under load, the 850 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 1600/7200 kN ratings and 52000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 89434 M in service?", "a": "Unloaded running below factor A 4.15 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 850 r/min limiting." }, { "q": "Which dimensions does the 89434 M have?", "a": "A 89434 M measures 170 mm bore × 340 mm outside diameter × 103 mm width (6.693 × 13.386 × 4.055 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1600 kN, static C0 7200 kN, fatigue limit Pu 600 kN, reference speed 430 r/min, limiting speed 850 r/min, mass about 52000 g. Raceway diameters Ea 191 mm / Eb 333 mm and minimum load factor A 4.15 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89434 M belongs to the extra-heavy 894 series, 170×340×103 mm." }, { "q": "Are the washers of 89434 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "89434", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89434-M", "89434 M" ], "locale_variants": {} }, { "sku": "81136-M", "brand": "SKF", "manufacturer_designation": "81136 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 180, "D_mm": 225, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 270, "static_load_kN": 1270, "fatigue_load_limit_kN": 110, "reference_speed_rpm": 750, "limiting_speed_rpm": 1500, "max_rpm": 1500, "weight_g": 3700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81136 M carries pure axial load at low to moderate speed: 270 kN dynamic and 1270 kN static across a 180×225 mm washer pair, 34 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81136 M sits in the light 811 series. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. Speed planning separates the 750 r/min thermal reference from the 1,500 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 180 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 34 mm.", "The 270/1270 kN ratings assume flat, full-support washer seats; a housing face narrower than the 225 mm washer OD invalidates the rating through edge stress.", "Factor A 0.13 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81136 M size.", "the 750 r/min reference speed is the thermal criterion under load, the 1,500 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 270/1270 kN ratings and 3700 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81136 M in service?", "a": "Unloaded running below factor A 0.13 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,500 r/min limiting." }, { "q": "Which dimensions does the 81136 M have?", "a": "A 81136 M measures 180 mm bore × 225 mm outside diameter × 34 mm width (7.087 × 8.858 × 1.339 in). From SKF catalogue PUB BU/P1 17000: dynamic C 270 kN, static C0 1270 kN, fatigue limit Pu 110 kN, reference speed 750 r/min, limiting speed 1,500 r/min, mass about 3700 g. Raceway diameters Ea 185 mm / Eb 219 mm and minimum load factor A 0.13 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81136 M belongs to the light 811 series, 180×225×34 mm." }, { "q": "Are the washers of 81136 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81136", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81136-M", "81136 M" ], "locale_variants": {} }, { "sku": "81236-M", "brand": "SKF", "manufacturer_designation": "81236 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 180, "D_mm": 250, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 550, "static_load_kN": 2400, "fatigue_load_limit_kN": 204, "reference_speed_rpm": 560, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 9950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81236 M is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 180×250×56 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81236 M sits in the heavy 812 series. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. The 9950 g mass and 56 mm axial height sit between 180 and 250 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "false brinelling and rust-red witness marks on standby machines under external vibration", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 180 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 56 mm.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81236 M size.", "the 560 r/min reference speed is the thermal criterion under load, the 1,100 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81236 M need different minimum load and lubrication despite the shared 180×250 mm outline.", "The 550/2400 kN ratings and 9950 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81236 M in service?", "a": "Unloaded running below factor A 0.46 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,100 r/min limiting." }, { "q": "Which dimensions does the 81236 M have?", "a": "A 81236 M measures 180 mm bore × 250 mm outside diameter × 56 mm width (7.087 × 9.843 × 2.205 in). From SKF catalogue PUB BU/P1 17000: dynamic C 550 kN, static C0 2400 kN, fatigue limit Pu 204 kN, reference speed 560 r/min, limiting speed 1,100 r/min, mass about 9950 g. Raceway diameters Ea 194 mm / Eb 243 mm and minimum load factor A 0.46 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81236 M belongs to the heavy 812 series, 180×250×56 mm." }, { "q": "Are the washers of 81236 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81236", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81236-M", "81236 M" ], "locale_variants": {} }, { "sku": "89436-M", "brand": "SKF", "manufacturer_designation": "89436 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 180, "D_mm": 360, "B_mm": 109, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1760, "static_load_kN": 8000, "fatigue_load_limit_kN": 655, "reference_speed_rpm": 400, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 60000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The extra-heavy 894 series bearing 89436 M carries pure axial load at low to moderate speed: 1760 kN dynamic and 8000 kN static across a 180×360 mm washer pair, 109 mm overall height. In 89436 M, 894 fixes the 360 mm OD and 109 mm height; 36 selects the 180 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. Static safety matters for shock duty: compare peak axial force against C0 8000 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 180 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 109 mm.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89436 M need different minimum load and lubrication despite the shared 180×360 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89436 M size.", "the 400 r/min reference speed is the thermal criterion under load, the 800 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 1760/8000 kN ratings assume flat, full-support washer seats; a housing face narrower than the 360 mm washer OD invalidates the rating through edge stress.", "The 1760/8000 kN ratings and 60000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 892); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 89436 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 5.1 minimum load is present." }, { "q": "What are the dimensions and ratings of the 89436 M?", "a": "A 89436 M measures 180 mm bore × 360 mm outside diameter × 109 mm width (7.087 × 14.173 × 4.291 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1760 kN, static C0 8000 kN, fatigue limit Pu 655 kN, reference speed 400 r/min, limiting speed 800 r/min, mass about 60000 g. Raceway diameters Ea 200 mm / Eb 351 mm and minimum load factor A 5.1 guide the seat design." }, { "q": "How is the 89436 M designation read?", "a": "The first three digits 894 give the dimension series (extra-heavy 894 series); 36 encodes the 180 mm bore (code 36 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 89436 M need a minimum axial load?", "a": "Below factor A 5.1 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "89436", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89436-M", "89436 M" ], "locale_variants": {} }, { "sku": "81138-M", "brand": "SKF", "manufacturer_designation": "81138 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 190, "D_mm": 240, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 310, "static_load_kN": 1460, "fatigue_load_limit_kN": 125, "reference_speed_rpm": 700, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 4750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81138 M carries pure axial load at low to moderate speed: 310 kN dynamic and 1460 kN static across a 190×240 mm washer pair, 37 mm overall height. In 81138 M, 811 fixes the 240 mm OD and 37 mm height; 38 selects the 190 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.17. Static safety matters for shock duty: compare peak axial force against C0 1460 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 190 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 37 mm.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81138 M need different minimum load and lubrication despite the shared 190×240 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81138 M size.", "the 700 r/min reference speed is the thermal criterion under load, the 1,400 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 310/1460 kN ratings assume flat, full-support washer seats; a housing face narrower than the 240 mm washer OD invalidates the rating through edge stress.", "The 310/1460 kN ratings and 4750 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81138 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.17 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81138 M?", "a": "A 81138 M measures 190 mm bore × 240 mm outside diameter × 37 mm width (7.48 × 9.449 × 1.457 in). From SKF catalogue PUB BU/P1 17000: dynamic C 310 kN, static C0 1460 kN, fatigue limit Pu 125 kN, reference speed 700 r/min, limiting speed 1,400 r/min, mass about 4750 g. Raceway diameters Ea 197 mm / Eb 233 mm and minimum load factor A 0.17 guide the seat design." }, { "q": "How is the 81138 M designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 38 encodes the 190 mm bore (code 38 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81138 M need a minimum axial load?", "a": "Below factor A 0.17 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81138", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81138-M", "81138 M" ], "locale_variants": {} }, { "sku": "81238-M", "brand": "SKF", "manufacturer_designation": "81238 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 190, "D_mm": 270, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 695, "static_load_kN": 2900, "fatigue_load_limit_kN": 250, "reference_speed_rpm": 500, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81238 M is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 190×270×62 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 38 encode the 190 mm shaft washer bore (code 38 × 5), and M names the cage execution. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 695 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 0.67: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. Mounting: locate the shaft washer on the 190 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 270 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 190 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 62 mm.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81238 M need different minimum load and lubrication despite the shared 190×270 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81238 M size.", "the 500 r/min reference speed is the thermal criterion under load, the 1,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 695/2900 kN ratings and 12000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Which dimensions does the 81238 M have?", "a": "A 81238 M measures 190 mm bore × 270 mm outside diameter × 62 mm width (7.48 × 10.63 × 2.441 in). From SKF catalogue PUB BU/P1 17000: dynamic C 695 kN, static C0 2900 kN, fatigue limit Pu 250 kN, reference speed 500 r/min, limiting speed 1,000 r/min, mass about 12000 g. Raceway diameters Ea 205 mm / Eb 263 mm and minimum load factor A 0.67 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81238 M belongs to the heavy 812 series, 190×270×62 mm." }, { "q": "Are the washers of 81238 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81238 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." } ], "cross_ref": [ { "equiv_sku": "81238", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81238-M", "81238 M" ], "locale_variants": {} }, { "sku": "89438-M", "brand": "SKF", "manufacturer_designation": "89438 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 190, "D_mm": 380, "B_mm": 115, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1960, "static_load_kN": 9000, "fatigue_load_limit_kN": 720, "reference_speed_rpm": 380, "limiting_speed_rpm": 750, "max_rpm": 750, "weight_g": 65500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 89438 M as a separable thrust bearing: the 190 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 380 mm housing washer (GS) can be ordered and mounted individually. The designation 89438 M states 894 series, 190 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 6.5. The 65500 g mass and 115 mm axial height sit between 190 and 380 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 6.5) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 190 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 115 mm.", "Factor A 6.5 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "the 380 r/min reference speed is the thermal criterion under load, the 750 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 1960/9000 kN ratings assume flat, full-support washer seats; a housing face narrower than the 380 mm washer OD invalidates the rating through edge stress.", "The 1960/9000 kN ratings and 65500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 89438 M?", "a": "A 89438 M measures 190 mm bore × 380 mm outside diameter × 115 mm width (7.48 × 14.961 × 4.528 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1960 kN, static C0 9000 kN, fatigue limit Pu 720 kN, reference speed 380 r/min, limiting speed 750 r/min, mass about 65500 g. Raceway diameters Ea 212 mm / Eb 371 mm and minimum load factor A 6.5 guide the seat design." }, { "q": "How is the 89438 M designation read?", "a": "The first three digits 894 give the dimension series (extra-heavy 894 series); 38 encodes the 190 mm bore (code 38 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 89438 M need a minimum axial load?", "a": "Below factor A 6.5 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 89438 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "89438", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89438-M", "89438 M" ], "locale_variants": {} }, { "sku": "81140-M", "brand": "SKF", "manufacturer_designation": "81140 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 200, "D_mm": 250, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 310, "static_load_kN": 1500, "fatigue_load_limit_kN": 125, "reference_speed_rpm": 700, "limiting_speed_rpm": 1400, "max_rpm": 1400, "weight_g": 4950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81140 M carries pure axial load at low to moderate speed: 310 kN dynamic and 1500 kN static across a 200×250 mm washer pair, 37 mm overall height. The designation 81140 M states 811 series, 200 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.18. Selection arithmetic: C 310 kN against C0 1500 kN gives a C0/C ratio of 4.84 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.18) is present without clamping the rollers.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "abrasive paste forming as dust bypasses the housing seals into the open washer set", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 200 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 37 mm.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81140 M need different minimum load and lubrication despite the shared 200×250 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81140 M size.", "The 310/1500 kN ratings assume flat, full-support washer seats; a housing face narrower than the 250 mm washer OD invalidates the rating through edge stress.", "Factor A 0.18 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The 310/1500 kN ratings and 4950 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Why does 81140 M need a minimum axial load?", "a": "Below factor A 0.18 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81140 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81140 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.18 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81140 M?", "a": "A 81140 M measures 200 mm bore × 250 mm outside diameter × 37 mm width (7.874 × 9.843 × 1.457 in). From SKF catalogue PUB BU/P1 17000: dynamic C 310 kN, static C0 1500 kN, fatigue limit Pu 125 kN, reference speed 700 r/min, limiting speed 1,400 r/min, mass about 4950 g. Raceway diameters Ea 206 mm / Eb 243 mm and minimum load factor A 0.18 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81140", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81140-M", "81140 M" ], "locale_variants": {} }, { "sku": "81240-M", "brand": "SKF", "manufacturer_designation": "81240 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 200, "D_mm": 280, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 720, "static_load_kN": 3100, "fatigue_load_limit_kN": 255, "reference_speed_rpm": 500, "limiting_speed_rpm": 1000, "max_rpm": 1000, "weight_g": 13500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81240 M as a separable thrust bearing: the 200 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 280 mm housing washer (GS) can be ordered and mounted individually. The designation 81240 M states 812 series, 200 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. The 13500 g mass and 62 mm axial height sit between 200 and 280 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 0.77) is present without clamping the rollers.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 200 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 62 mm.", "Factor A 0.77 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "the 500 r/min reference speed is the thermal criterion under load, the 1,000 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 720/3100 kN ratings assume flat, full-support washer seats; a housing face narrower than the 280 mm washer OD invalidates the rating through edge stress.", "The 720/3100 kN ratings and 13500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81240 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81240 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.77 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81240 M?", "a": "A 81240 M measures 200 mm bore × 280 mm outside diameter × 62 mm width (7.874 × 11.024 × 2.441 in). From SKF catalogue PUB BU/P1 17000: dynamic C 720 kN, static C0 3100 kN, fatigue limit Pu 255 kN, reference speed 500 r/min, limiting speed 1,000 r/min, mass about 13500 g. Raceway diameters Ea 215 mm / Eb 273 mm and minimum load factor A 0.77 guide the seat design." }, { "q": "How is the 81240 M designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 40 encodes the 200 mm bore (code 40 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81240", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81240-M", "81240 M" ], "locale_variants": {} }, { "sku": "89440-M", "brand": "SKF", "manufacturer_designation": "89440 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 200, "D_mm": 400, "B_mm": 122, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2160, "static_load_kN": 10000, "fatigue_load_limit_kN": 800, "reference_speed_rpm": 360, "limiting_speed_rpm": 700, "max_rpm": 700, "weight_g": 75000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The extra-heavy 894 series bearing 89440 M carries pure axial load at low to moderate speed: 2160 kN dynamic and 10000 kN static across a 200×400 mm washer pair, 122 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 89440 M sits in the extra-heavy 894 series. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 2160 kN rating assumes oil or grease reaching the full washer face. Static safety matters for shock duty: compare peak axial force against C0 10000 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 200 mm bore the washers are too stiff to conform to a non-square seat: machine the shoulders parallel or the roller ends concentrate load into a narrow stripe across 122 mm.", "The 2160/10000 kN ratings assume flat, full-support washer seats; a housing face narrower than the 400 mm washer OD invalidates the rating through edge stress.", "Factor A 8 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89440 M need different minimum load and lubrication despite the shared 200×400 mm outline.", "The 2160/10000 kN ratings and 75000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 89440 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 89440 M in service?", "a": "Unloaded running below factor A 8 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 700 r/min limiting." }, { "q": "Which dimensions does the 89440 M have?", "a": "A 89440 M measures 200 mm bore × 400 mm outside diameter × 122 mm width (7.874 × 15.748 × 4.803 in). From SKF catalogue PUB BU/P1 17000: dynamic C 2160 kN, static C0 10000 kN, fatigue limit Pu 800 kN, reference speed 360 r/min, limiting speed 700 r/min, mass about 75000 g. Raceway diameters Ea 224 mm / Eb 391 mm and minimum load factor A 8 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 89440 M belongs to the extra-heavy 894 series, 200×400×122 mm." } ], "cross_ref": [ { "equiv_sku": "89440", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89440-M", "89440 M" ], "locale_variants": {} }, { "sku": "81144-M", "brand": "SKF", "manufacturer_designation": "81144 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 220, "D_mm": 270, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 335, "static_load_kN": 1700, "fatigue_load_limit_kN": 137, "reference_speed_rpm": 670, "limiting_speed_rpm": 1300, "max_rpm": 1300, "weight_g": 5200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81144 M carries pure axial load at low to moderate speed: 335 kN dynamic and 1700 kN static across a 220×270 mm washer pair, 37 mm overall height. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 44 encode the 220 mm shaft washer bore (code 44 × 5), and M names the cage execution. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 335 kN rating assumes oil or grease reaching the full washer face. Minimum axial load is explicit at factor A 0.23: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 220 mm bore the 5.2 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81144 M size.", "the 670 r/min reference speed is the thermal criterion under load, the 1,300 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Factor A 0.23 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 335/1700 kN ratings and 5200 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81144 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81144 M in service?", "a": "Unloaded running below factor A 0.23 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,300 r/min limiting." }, { "q": "Which dimensions does the 81144 M have?", "a": "A 81144 M measures 220 mm bore × 270 mm outside diameter × 37 mm width (8.661 × 10.63 × 1.457 in). From SKF catalogue PUB BU/P1 17000: dynamic C 335 kN, static C0 1700 kN, fatigue limit Pu 137 kN, reference speed 670 r/min, limiting speed 1,300 r/min, mass about 5200 g. Raceway diameters Ea 226 mm / Eb 263 mm and minimum load factor A 0.23 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81144 M belongs to the light 811 series, 220×270×37 mm." } ], "cross_ref": [ { "equiv_sku": "81144", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81144-M", "81144 M" ], "locale_variants": {} }, { "sku": "81244-M", "brand": "SKF", "manufacturer_designation": "81244 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 220, "D_mm": 300, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 750, "static_load_kN": 3350, "fatigue_load_limit_kN": 275, "reference_speed_rpm": 480, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81244 M is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 220×300×63 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 44 encode the 220 mm shaft washer bore (code 44 × 5), and M names the cage execution. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. One direction only: 81244 M cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Mounting: locate the shaft washer on the 220 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 300 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 220 mm bore the 15 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81244 M need different minimum load and lubrication despite the shared 220×300 mm outline.", "The 750/3350 kN ratings assume flat, full-support washer seats; a housing face narrower than the 300 mm washer OD invalidates the rating through edge stress.", "Factor A 0.9 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "The 750/3350 kN ratings and 15000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What ruins a 81244 M in service?", "a": "Unloaded running below factor A 0.9 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 950 r/min limiting." }, { "q": "Which dimensions does the 81244 M have?", "a": "A 81244 M measures 220 mm bore × 300 mm outside diameter × 63 mm width (8.661 × 11.811 × 2.48 in). From SKF catalogue PUB BU/P1 17000: dynamic C 750 kN, static C0 3350 kN, fatigue limit Pu 275 kN, reference speed 480 r/min, limiting speed 950 r/min, mass about 15000 g. Raceway diameters Ea 236 mm / Eb 294 mm and minimum load factor A 0.9 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81244 M belongs to the heavy 812 series, 220×300×63 mm." }, { "q": "Are the washers of 81244 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." } ], "cross_ref": [ { "equiv_sku": "81244", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81244-M", "81244 M" ], "locale_variants": {} }, { "sku": "89444-M", "brand": "SKF", "manufacturer_designation": "89444 M", "series": "89400-series", "type": "cylindrical_roller_thrust", "d_mm": 220, "D_mm": 420, "B_mm": 122, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2320, "static_load_kN": 11200, "fatigue_load_limit_kN": 880, "reference_speed_rpm": 340, "limiting_speed_rpm": 700, "max_rpm": 700, "weight_g": 84500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 89444 M as a separable thrust bearing: the 220 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 420 mm housing washer (GS) can be ordered and mounted individually. The designation 89444 M states 894 series, 220 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 2320 kN rating assumes oil or grease reaching the full washer face. Selection arithmetic: C 2320 kN against C0 11200 kN gives a C0/C ratio of 4.83 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 10) is present without clamping the rollers.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 220 mm bore the 84.5 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Factor A 10 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 89444 M need different minimum load and lubrication despite the shared 220×420 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 89444 M size.", "The 2320/11200 kN ratings and 84500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 89444 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 10 minimum load is present." }, { "q": "What are the dimensions and ratings of the 89444 M?", "a": "A 89444 M measures 220 mm bore × 420 mm outside diameter × 122 mm width (8.661 × 16.535 × 4.803 in). From SKF catalogue PUB BU/P1 17000: dynamic C 2320 kN, static C0 11200 kN, fatigue limit Pu 880 kN, reference speed 340 r/min, limiting speed 700 r/min, mass about 84500 g. Raceway diameters Ea 244 mm / Eb 411 mm and minimum load factor A 10 guide the seat design." }, { "q": "How is the 89444 M designation read?", "a": "The first three digits 894 give the dimension series (extra-heavy 894 series); 44 encodes the 220 mm bore (code 44 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 89444 M need a minimum axial load?", "a": "Below factor A 10 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "89444", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "89444-M", "89444 M" ], "locale_variants": {} }, { "sku": "81148-M", "brand": "SKF", "manufacturer_designation": "81148 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 240, "D_mm": 300, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 475, "static_load_kN": 2450, "fatigue_load_limit_kN": 196, "reference_speed_rpm": 560, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 8450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81148 M carries pure axial load at low to moderate speed: 475 kN dynamic and 2450 kN static across a 240×300 mm washer pair, 45 mm overall height. In 81148 M, 811 fixes the 300 mm OD and 45 mm height; 48 selects the 240 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. The three components are separable and interchangeable within the size: WS shaft washer, K-cage roller set, GS housing washer, all running on flat, square seats; the machined brass M cage is standard for this size. Static safety matters for shock duty: compare peak axial force against C0 2450 kN with the application's static factor, since crane hooks and screw positions see their worst load at zero or low speed. Mounting: locate the shaft washer on the 240 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 300 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "washer back-face fretting where the seat is too narrow to support the full ring face", "grease churning and overheating when a high-speed thrust position is over-packed", "rolling-contact fatigue spalling after the catalogue L10 life is exhausted", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 240 mm bore the 8.4 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "the 560 r/min reference speed is the thermal criterion under load, the 1,100 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 475/2450 kN ratings assume flat, full-support washer seats; a housing face narrower than the 300 mm washer OD invalidates the rating through edge stress.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81148 M need different minimum load and lubrication despite the shared 240×300 mm outline.", "The 475/2450 kN ratings and 8450 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "How should a 81148 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 0.48 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81148 M?", "a": "A 81148 M measures 240 mm bore × 300 mm outside diameter × 45 mm width (9.449 × 11.811 × 1.772 in). From SKF catalogue PUB BU/P1 17000: dynamic C 475 kN, static C0 2450 kN, fatigue limit Pu 196 kN, reference speed 560 r/min, limiting speed 1,100 r/min, mass about 8450 g. Raceway diameters Ea 248 mm / Eb 296 mm and minimum load factor A 0.48 guide the seat design." }, { "q": "How is the 81148 M designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 48 encodes the 240 mm bore (code 48 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81148 M need a minimum axial load?", "a": "Below factor A 0.48 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." } ], "cross_ref": [ { "equiv_sku": "81148", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81148-M", "81148 M" ], "locale_variants": {} }, { "sku": "81248-M", "brand": "SKF", "manufacturer_designation": "81248 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 240, "D_mm": 340, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1100, "static_load_kN": 4900, "fatigue_load_limit_kN": 390, "reference_speed_rpm": 400, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 22000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81248 M is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 240×340×78 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. In 81248 M, 812 fixes the 340 mm OD and 78 mm height; 48 selects the 240 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 78 mm height. Speed planning separates the 400 r/min thermal reference from the 800 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 1.92) is present without clamping the rollers.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "housing-washer rotation scored into an unmachined or loose seating face", "grease churning and overheating when a high-speed thrust position is over-packed", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 240 mm bore the 22 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81248 M need different minimum load and lubrication despite the shared 240×340 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81248 M size.", "Factor A 1.92 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 1100/4900 kN ratings and 22000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "What are the dimensions and ratings of the 81248 M?", "a": "A 81248 M measures 240 mm bore × 340 mm outside diameter × 78 mm width (9.449 × 13.386 × 3.071 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1100 kN, static C0 4900 kN, fatigue limit Pu 390 kN, reference speed 400 r/min, limiting speed 800 r/min, mass about 22000 g. Raceway diameters Ea 263 mm / Eb 333 mm and minimum load factor A 1.92 guide the seat design." }, { "q": "How is the 81248 M designation read?", "a": "The first three digits 812 give the dimension series (heavy 812 series); 48 encodes the 240 mm bore (code 48 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." }, { "q": "Why does 81248 M need a minimum axial load?", "a": "Below factor A 1.92 the cylindrical rollers skid instead of rolling, glazing and smearing the washer tracks. Springs, preload shims or rotor weight must keep the thrust above the catalogue minimum, especially during unloaded starts." }, { "q": "Can the 81248 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." } ], "cross_ref": [ { "equiv_sku": "81248", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81248-M", "81248 M" ], "locale_variants": {} }, { "sku": "81152-M", "brand": "SKF", "manufacturer_designation": "81152 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 260, "D_mm": 320, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 490, "static_load_kN": 2600, "fatigue_load_limit_kN": 200, "reference_speed_rpm": 530, "limiting_speed_rpm": 1100, "max_rpm": 1100, "weight_g": 9100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "The light 811 series bearing 81152 M carries pure axial load at low to moderate speed: 490 kN dynamic and 2600 kN static across a 260×320 mm washer pair, 45 mm overall height. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81152 M sits in the light 811 series. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 0.54. The 9100 g mass and 45 mm axial height sit between 260 and 320 mm washer diameters; check the seat shoulder spans the full ring face — a narrow shoulder causes washer fretting long before fatigue does. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels" ], "failure_modes": [ "cage wear from rollers being dragged through unloaded zones under fluctuating thrust", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "false brinelling and rust-red witness marks on standby machines under external vibration", "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)" ], "pitfalls": [ "At 260 mm bore the 9.1 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81152 M need different minimum load and lubrication despite the shared 260×320 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81152 M size.", "the 530 r/min reference speed is the thermal criterion under load, the 1,100 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 490/2600 kN ratings and 9100 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81152 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81152 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81152 M in service?", "a": "Unloaded running below factor A 0.54 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 1,100 r/min limiting." }, { "q": "Which dimensions does the 81152 M have?", "a": "A 81152 M measures 260 mm bore × 320 mm outside diameter × 45 mm width (10.236 × 12.598 × 1.772 in). From SKF catalogue PUB BU/P1 17000: dynamic C 490 kN, static C0 2600 kN, fatigue limit Pu 200 kN, reference speed 530 r/min, limiting speed 1,100 r/min, mass about 9100 g. Raceway diameters Ea 268 mm / Eb 316 mm and minimum load factor A 0.54 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81152", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81152-M", "81152 M" ], "locale_variants": {} }, { "sku": "81252-M", "brand": "SKF", "manufacturer_designation": "81252 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 260, "D_mm": 360, "B_mm": 79, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1140, "static_load_kN": 5300, "fatigue_load_limit_kN": 415, "reference_speed_rpm": 380, "limiting_speed_rpm": 750, "max_rpm": 750, "weight_g": 27000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "81252 M is a single-direction cylindrical roller thrust bearing to ISO 104 in the heavy 812 series: a flat shaft washer, a roller-and-cage set and a housing washer stacked to 260×360×79 mm, listed in SKF catalogue PUB BU/P1 17000 ch. 11.1. SKF thrust-roller numbering mirrors the ball 511/512 plan with 811/812: 812 is the higher (heavier) section per bore, and 893/894 are the very heavy series — 81252 M sits in the heavy 812 series. Small sizes ship with machined brass M cages to guide heavy rollers at the lubricant limit; the 1140 kN rating assumes oil or grease reaching the full washer face. Selection arithmetic: C 1140 kN against C0 5300 kN gives a C0/C ratio of 4.65 — thrust bearings are chosen on static rating and F_a/C0 more often than on L10 life. Mounting: locate the shaft washer on the 260 mm seat (it rotates and takes an interference fit), leave the housing washer a sliding fit in the 360 mm bore, and check the stack can tilt freely before clamping.", "applications": [ "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "hard-particle indentation where oil or grease filtration is inadequate", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 260 mm bore the 27 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "The 1140/5300 kN ratings assume flat, full-support washer seats; a housing face narrower than the 360 mm washer OD invalidates the rating through edge stress.", "Factor A 2.25 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81252 M need different minimum load and lubrication despite the shared 260×360 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81252 M size.", "The 1140/5300 kN ratings and 27000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81252 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81252 M in service?", "a": "Unloaded running below factor A 2.25 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 750 r/min limiting." }, { "q": "Which dimensions does the 81252 M have?", "a": "A 81252 M measures 260 mm bore × 360 mm outside diameter × 79 mm width (10.236 × 14.173 × 3.11 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1140 kN, static C0 5300 kN, fatigue limit Pu 415 kN, reference speed 380 r/min, limiting speed 750 r/min, mass about 27000 g. Raceway diameters Ea 281 mm / Eb 351 mm and minimum load factor A 2.25 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81252 M belongs to the heavy 812 series, 260×360×79 mm." } ], "cross_ref": [ { "equiv_sku": "81252", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81252-M", "81252 M" ], "locale_variants": {} }, { "sku": "81156-M", "brand": "SKF", "manufacturer_designation": "81156 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 280, "D_mm": 350, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 680, "static_load_kN": 3550, "fatigue_load_limit_kN": 275, "reference_speed_rpm": 480, "limiting_speed_rpm": 950, "max_rpm": 950, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81156 M as a separable thrust bearing: the 280 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 350 mm housing washer (GS) can be ordered and mounted individually. The designation 81156 M states 811 series, 280 mm bore, machined brass M cage; shaft and housing washers are also orderable separately as WS and GS parts of the same size. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 1. One direction only: 81156 M cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 1) is present without clamping the rollers.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "brinelling of washer raceways from impact or mounting force applied through the rolling elements", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 280 mm bore the 12.5 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81156 M need different minimum load and lubrication despite the shared 280×350 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81156 M size.", "the 480 r/min reference speed is the thermal criterion under load, the 950 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "The 680/3550 kN ratings assume flat, full-support washer seats; a housing face narrower than the 350 mm washer OD invalidates the rating through edge stress.", "The 680/3550 kN ratings and 12500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81156 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81156 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 1 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81156 M?", "a": "A 81156 M measures 280 mm bore × 350 mm outside diameter × 53 mm width (11.024 × 13.78 × 2.087 in). From SKF catalogue PUB BU/P1 17000: dynamic C 680 kN, static C0 3550 kN, fatigue limit Pu 275 kN, reference speed 480 r/min, limiting speed 950 r/min, mass about 12500 g. Raceway diameters Ea 288 mm / Eb 346 mm and minimum load factor A 1 guide the seat design." }, { "q": "How is the 81156 M designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 56 encodes the 280 mm bore (code 56 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81156", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81156-M", "81156 M" ], "locale_variants": {} }, { "sku": "81160-M", "brand": "SKF", "manufacturer_designation": "81160 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 300, "D_mm": 380, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 850, "static_load_kN": 4400, "fatigue_load_limit_kN": 335, "reference_speed_rpm": 430, "limiting_speed_rpm": 850, "max_rpm": 850, "weight_g": 19500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81160 M as a separable thrust bearing: the 300 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 380 mm housing washer (GS) can be ordered and mounted individually. Reading the code: the first three digits 811 give the dimension series (light 811 series), the last two 60 encode the 300 mm shaft washer bore (code 60 × 5), and M names the cage execution. Rigid washers mean no self-alignment: the shaft and housing shoulders must be square and parallel to within the catalogue seat tolerances, or the rollers edge-load across the 62 mm height. One direction only: 81160 M cannot be reversed to take opposite thrust — mirror a second bearing for reversing shafts, and keep housing and shaft seats square within the ISO 104 tolerances. Press only on washer backs, never through the roller set; seat both washers against full-area square shoulders, and shim the housing cover so the minimum load (A 1.55) is present without clamping the rollers.", "applications": [ "slewing and turntable pivots with predominantly axial force", "crane hook crossheads carrying pure hook thrust while the hook swivels", "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing" ], "failure_modes": [ "roller skidding and raceway glazing once the thrust falls below the catalogue minimum axial load (factor A)", "washer back-face fretting where the seat is too narrow to support the full ring face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "electrical erosion of raceways on VFD-driven shafts without grounding or insulation", "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established" ], "pitfalls": [ "At 300 mm bore the 19.5 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "The 850/4400 kN ratings assume flat, full-support washer seats; a housing face narrower than the 380 mm washer OD invalidates the rating through edge stress.", "Factor A 1.55 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81160 M need different minimum load and lubrication despite the shared 300×380 mm outline.", "The 850/4400 kN ratings and 19500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Are the washers of 81160 M separable?", "a": "Yes — shaft washer WS, roller-and-cage set and housing washer GS are separate and interchangeable within the size, but never across series: an 811 and an 812 washer for the same bore differ in OD and height." }, { "q": "Can a thrust ball bearing replace the 81160 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81160 M in service?", "a": "Unloaded running below factor A 1.55 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 850 r/min limiting." }, { "q": "Which dimensions does the 81160 M have?", "a": "A 81160 M measures 300 mm bore × 380 mm outside diameter × 62 mm width (11.811 × 14.961 × 2.441 in). From SKF catalogue PUB BU/P1 17000: dynamic C 850 kN, static C0 4400 kN, fatigue limit Pu 335 kN, reference speed 430 r/min, limiting speed 850 r/min, mass about 19500 g. Raceway diameters Ea 315 mm / Eb 373 mm and minimum load factor A 1.55 guide the seat design." } ], "cross_ref": [ { "equiv_sku": "81160", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81160-M", "81160 M" ], "locale_variants": {} }, { "sku": "81260-M", "brand": "SKF", "manufacturer_designation": "81260 M", "series": "81200-series", "type": "cylindrical_roller_thrust", "d_mm": 300, "D_mm": 420, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1530, "static_load_kN": 7200, "fatigue_load_limit_kN": 540, "reference_speed_rpm": 320, "limiting_speed_rpm": 630, "max_rpm": 630, "weight_g": 43000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "Where a thrust ball bearing of the same envelope is exhausted, 81260 M replaces the ball complement with cylindrical rollers: 300 mm bore, 420 mm OD, rated 7200 kN static for steady hook and screw loads. Reading the code: the first three digits 812 give the dimension series (heavy 812 series), the last two 60 encode the 300 mm shaft washer bore (code 60 × 5), and M names the cage execution. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 4.1. Minimum axial load is explicit at factor A 4.1: below F_am = A·n² (or the catalogue's slow-speed floor) the cylindrical rollers skid; springs or the rotor's own weight are part of the selection, not an accessory. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters", "slewing and turntable pivots with predominantly axial force" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "housing-washer rotation scored into an unmachined or loose seating face", "oil starvation at the sliding contact zones of large spherical roller thrust bearings on forced-feed trips", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 300 mm bore the 43 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81260 M size.", "the 320 r/min reference speed is the thermal criterion under load, the 630 r/min limiting speed is mechanical and oil lubrication typically raises the usable figure.", "Factor A 4.1 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "The 1530/7200 kN ratings and 43000 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can a thrust ball bearing replace the 81260 M?", "a": "They share ISO boundary outlines (e.g. 511 vs 811), but the roller bearing needs a higher minimum axial load and different lubrication, and its C/C0 figures are not interchangeable — re-run the selection before substituting." }, { "q": "What ruins a 81260 M in service?", "a": "Unloaded running below factor A 4.1 causes skidding; non-square or narrow shoulders fret the washer backs; dry starts and contamination do the rest. Speed ceiling: 630 r/min limiting." }, { "q": "Which dimensions does the 81260 M have?", "a": "A 81260 M measures 300 mm bore × 420 mm outside diameter × 95 mm width (11.811 × 16.535 × 3.74 in). From SKF catalogue PUB BU/P1 17000: dynamic C 1530 kN, static C0 7200 kN, fatigue limit Pu 540 kN, reference speed 320 r/min, limiting speed 630 r/min, mass about 43000 g. Raceway diameters Ea 329 mm / Eb 412 mm and minimum load factor A 4.1 guide the seat design." }, { "q": "What is the difference between 811 and 812 series?", "a": "811 is the light section and 812 the higher, heavier section for the same bore; 893/894 are the extra-heavy series. 81260 M belongs to the heavy 812 series, 300×420×95 mm." } ], "cross_ref": [ { "equiv_sku": "81260", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81260-M", "81260 M" ], "locale_variants": {} }, { "sku": "81164-M", "brand": "SKF", "manufacturer_designation": "81164 M", "series": "81100-series", "type": "cylindrical_roller_thrust", "d_mm": 320, "D_mm": 400, "B_mm": 63, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 880, "static_load_kN": 4650, "fatigue_load_limit_kN": 345, "reference_speed_rpm": 400, "limiting_speed_rpm": 800, "max_rpm": 800, "weight_g": 20500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 104", "naming_rule_text": "SKF supplies 81164 M as a separable thrust bearing: the 320 mm shaft washer (WS), the machined brass M cage holding short cylindrical rollers, and the 400 mm housing washer (GS) can be ordered and mounted individually. In 81164 M, 811 fixes the 400 mm OD and 63 mm height; 64 selects the 320 mm seat, and the machined brass M cage is the only execution suffix on these rigid-washer bearings. The bearing takes thrust in one direction only — reverse loads lift the roller set off its track; arrange a mirrored second bearing for reversing duty, and keep the applied load above factor A 1.73. Speed planning separates the 400 r/min thermal reference from the 800 r/min mechanical limiting speed. Thrust bearings govern the thermal speed of many vertical arrangements, and oil circulation raises the usable speed substantially above grease values. In vertical shafts let the rotor weight provide the minimum load where possible; otherwise fit a spring pack above the housing washer, and verify the washer face is flooded with oil at first start.", "applications": [ "screw jack and lifting screw thrust positions under slow, steady load", "vertical electric motor and pump shafts whose rotor weight loads one bearing", "extruder and injection press screw thrust blocks at low speed", "rolling-mill screwdown mechanisms and press adjusters" ], "failure_modes": [ "smearing at roller-raceway contacts during unloaded startup before the oil film or preload is established", "shaft-washer creep and fretting corrosion on a soft or undersized shaft shoulder", "grease churning and overheating when a high-speed thrust position is over-packed", "condensation pitting in machines that run intermittently in humid environments", "cage wear from rollers being dragged through unloaded zones under fluctuating thrust" ], "pitfalls": [ "At 320 mm bore the 20.5 kg washer set needs forced lubrication and controlled start-up sequencing; dry first rotation under load is the classic destruction mode for very large thrust bearings.", "Factor A 1.73 is a mounting requirement, not advice: below the minimum axial load the rollers skid at speed — most \"mysterious\" early thrust failures are unloaded running.", "Keep the machined brass M cage out of chemical contact with aggressive EP additives beyond its compatibility list; cage damage here redistributes rollers and destroys the washer in hours.", "Do not substitute a thrust ball bearing of the same ISO envelope by rating alone: the cylindrical rollers of 81164 M need different minimum load and lubrication despite the shared 320×400 mm outline.", "The separable washers are not interchangeable across series: an 811 and an 812 washer for the same bore differ in OD and height — order WS/GS parts by the full 81164 M size.", "The 880/4650 kN ratings and 20500 g mass are SKF catalogue values transcribed from ch. 11.1 of PUB BU/P1 17000 (PDF table page 894); mounting data — Ea/Eb raceway diameters and the minimum load factor A — appears in the running text because the structured record carries the boundary envelope only." ], "faq": [ { "q": "Can the 81164 M take reversing thrust?", "a": "No. It carries axial load in one direction only; reversing force unloads and impacts the roller set. Use a mirrored pair of bearings for reversing shafts, with a separate arrangement for radial load." }, { "q": "How should a 81164 M be mounted?", "a": "Interference fit for the shaft washer, sliding fit for the housing washer, full-area square shoulders both sides, press on washer backs only, and shim the cover so the rollers turn freely while the factor-A 1.73 minimum load is present." }, { "q": "What are the dimensions and ratings of the 81164 M?", "a": "A 81164 M measures 320 mm bore × 400 mm outside diameter × 63 mm width (12.598 × 15.748 × 2.48 in). From SKF catalogue PUB BU/P1 17000: dynamic C 880 kN, static C0 4650 kN, fatigue limit Pu 345 kN, reference speed 400 r/min, limiting speed 800 r/min, mass about 20500 g. Raceway diameters Ea 334 mm / Eb 394 mm and minimum load factor A 1.73 guide the seat design." }, { "q": "How is the 81164 M designation read?", "a": "The first three digits 811 give the dimension series (light 811 series); 64 encodes the 320 mm bore (code 64 × 5); the suffix denotes the machined brass M cage. WS and GS washers of the same size can be ordered separately." } ], "cross_ref": [ { "equiv_sku": "81164", "equiv_brand": "ISO 15", "level": "full", "note": "ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 11.1 cylindrical roller thrust bearings", "extracted_at": "2026-09-27", "last_verified": "2026-09-27", "confidence_score": 0.7, "status": "published", "aliases": [ "81164-M", "81164 M" ], "locale_variants": {} } ]