[ { "sku": "NNCF4830-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4830 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 190, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 255, "static_load_kN": 585, "fatigue_load_limit_kN": 60, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 2800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4830 CV is a double-row full-complement cylindrical roller bearing sized 150×190×40 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 255 kN and C0 585 kN, size the bearing on the 150×190 mm ISO 15 envelope and check the 60 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 1,800 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 255/585 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4830-CV?", "a": "SKF NNCF 4830 CV is a double-row full-complement cylindrical roller bearing with 150 mm bore, 190 mm OD and 40 mm width per ISO 15. SKF lists C 255 kN, C0 585 kN, Pu 60 kN, reference speed 1,500 r/min and limiting speed 1,800 r/min, mass about 2800 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4830-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4830-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4830-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×190×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4830-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×190×40 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4830-CV", "SKF NNCF 4830 CV" ], "locale_variants": {} }, { "sku": "NNCF4832-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4832 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 200, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 260, "static_load_kN": 610, "fatigue_load_limit_kN": 62, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 3000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4832 CV resolves to a 160×200×40 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 20.0 mm and the catalogue mass 3000 g; at 260 kN dynamic rating this is roughly 1.63 kN of C per millimetre of bore before application factors. Fit practice for NNCF4832-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 260/610 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4832-CV?", "a": "SKF NNCF 4832 CV is a double-row full-complement cylindrical roller bearing with 160 mm bore, 200 mm OD and 40 mm width per ISO 15. SKF lists C 260 kN, C0 610 kN, Pu 62 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 3000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4832-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4832-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4832-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×200×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4832-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×200×40 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4832-CV", "SKF NNCF 4832 CV" ], "locale_variants": {} }, { "sku": "NNCF4834-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4834 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 215, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 286, "static_load_kN": 655, "fatigue_load_limit_kN": 65.5, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 170 mm shaft, SKF lists NNCF4834-CV as double-row full-complement cylindrical roller: 215 mm OD, 45 mm wide, Pu 65.5 kN, the catalogue lists 1,300 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 22.5 mm and the catalogue mass 4000 g; at 286 kN dynamic rating this is roughly 1.68 kN of C per millimetre of bore before application factors. Fit practice for NNCF4834-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 286/655 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4834-CV?", "a": "SKF NNCF 4834 CV is a double-row full-complement cylindrical roller bearing with 170 mm bore, 215 mm OD and 45 mm width per ISO 15. SKF lists C 286 kN, C0 655 kN, Pu 65.5 kN, reference speed 1,300 r/min and limiting speed 1,600 r/min, mass about 4000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4834-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4834-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4834-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×215×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4834-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×215×45 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4834-CV", "SKF NNCF 4834 CV" ], "locale_variants": {} }, { "sku": "NNCF4836-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4836 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 225, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 297, "static_load_kN": 695, "fatigue_load_limit_kN": 69.5, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 4200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4836 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 180×225×45 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 4200 g. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 22.5 mm and the catalogue mass 4200 g; at 297 kN dynamic rating this is roughly 1.65 kN of C per millimetre of bore before application factors. Fit practice for NNCF4836-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 225 mm raceway.", "The 297/695 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4836-CV?", "a": "SKF NNCF 4836 CV is a double-row full-complement cylindrical roller bearing with 180 mm bore, 225 mm OD and 45 mm width per ISO 15. SKF lists C 297 kN, C0 695 kN, Pu 69.5 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 4200 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4836-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4836-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4836-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×225×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4836-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×225×45 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4836-CV", "SKF NNCF 4836 CV" ], "locale_variants": {} }, { "sku": "NNCF4838-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4838 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 240, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 358, "static_load_kN": 750, "fatigue_load_limit_kN": 76.5, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 5500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4838-CV is the 190 mm bore entry in the NNCF4800 range: a 190×240×50 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 358 kN / C0 750 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 25.0 mm and the catalogue mass 5500 g; at 358 kN dynamic rating this is roughly 1.88 kN of C per millimetre of bore before application factors. Fit practice for NNCF4838-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "The 358/750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4838-CV?", "a": "SKF NNCF 4838 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 358 kN, C0 750 kN, Pu 76.5 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 5500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4838-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4838-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4838-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×240×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4838-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×240×50 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4838-CV", "SKF NNCF 4838 CV" ], "locale_variants": {} }, { "sku": "NNCF4840-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4840 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 250, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 369, "static_load_kN": 800, "fatigue_load_limit_kN": 80, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 5800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4840 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 200×250×50 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 5800 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCF4840-CV: the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. The mass entry 5800 g covers the complete catalogue execution. Fit practice for NNCF4840-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 369/800 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4840-CV?", "a": "SKF NNCF 4840 CV is a double-row full-complement cylindrical roller bearing with 200 mm bore, 250 mm OD and 50 mm width per ISO 15. SKF lists C 369 kN, C0 800 kN, Pu 80 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 5800 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4840-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4840-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4840-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×250×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4840-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×250×50 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4840-CV", "SKF NNCF 4840 CV" ], "locale_variants": {} }, { "sku": "NNCF4844-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4844 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 270, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 380, "static_load_kN": 865, "fatigue_load_limit_kN": 85, "max_rpm": 1200, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1200, "weight_g": 6300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4844 CV is a double-row full-complement cylindrical roller bearing sized 220×270×50 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 380 kN and C0 865 kN, size the bearing on the 220×270 mm ISO 15 envelope and check the 85 kN Pu against the equivalent-load floor; the catalogue lists 1,000 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 380/865 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4844-CV?", "a": "SKF NNCF 4844 CV is a double-row full-complement cylindrical roller bearing with 220 mm bore, 270 mm OD and 50 mm width per ISO 15. SKF lists C 380 kN, C0 865 kN, Pu 85 kN, reference speed 1,000 r/min and limiting speed 1,200 r/min, mass about 6300 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4844-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4844-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4844-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×270×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4844-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×270×50 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4844-CV", "SKF NNCF 4844 CV" ], "locale_variants": {} }, { "sku": "NNCF4848-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4848 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 300, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 539, "static_load_kN": 1290, "fatigue_load_limit_kN": 125, "max_rpm": 1100, "reference_speed_rpm": 900, "limiting_speed_rpm": 1100, "weight_g": 9900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 240 mm shaft, SKF lists NNCF4848-CV as double-row full-complement cylindrical roller: 300 mm OD, 60 mm wide, Pu 125 kN, the catalogue lists 900 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 539 kN and C0 1290 kN, size the bearing on the 240×300 mm ISO 15 envelope and check the 125 kN Pu against the equivalent-load floor; the catalogue lists 900 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 240 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 539/1290 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4848-CV?", "a": "SKF NNCF 4848 CV is a double-row full-complement cylindrical roller bearing with 240 mm bore, 300 mm OD and 60 mm width per ISO 15. SKF lists C 539 kN, C0 1290 kN, Pu 125 kN, reference speed 900 r/min and limiting speed 1,100 r/min, mass about 9900 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4848-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4848-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4848-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×300×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4848-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×300×60 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4848-CV", "SKF NNCF 4848 CV" ], "locale_variants": {} }, { "sku": "NNCF4852-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4852 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 320, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 561, "static_load_kN": 1400, "fatigue_load_limit_kN": 132, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4852-CV is the 260 mm bore entry in the NNCF4800 range: a 260×320×60 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 561 kN / C0 1400 kN. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF4852-CV: the catalogue lists 800 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. The mass entry 11000 g covers the complete catalogue execution. Fit practice for NNCF4852-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 561/1400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4852-CV?", "a": "SKF NNCF 4852 CV is a double-row full-complement cylindrical roller bearing with 260 mm bore, 320 mm OD and 60 mm width per ISO 15. SKF lists C 561 kN, C0 1400 kN, Pu 132 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 11000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4852-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4852-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4852-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×320×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4852-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×320×60 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4852-CV", "SKF NNCF 4852 CV" ], "locale_variants": {} }, { "sku": "NNCF4856-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4856 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 350, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 737, "static_load_kN": 1860, "fatigue_load_limit_kN": 173, "max_rpm": 950, "reference_speed_rpm": 750, "limiting_speed_rpm": 950, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4856 CV resolves to a 280×350×69 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF4856-CV: the catalogue lists 750 r/min thermal reference speed and 950 r/min mechanical limiting speed. The mass entry 16000 g covers the complete catalogue execution. Fit practice for NNCF4856-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 350 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 350 mm raceway.", "The 737/1860 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4856-CV?", "a": "SKF NNCF 4856 CV is a double-row full-complement cylindrical roller bearing with 280 mm bore, 350 mm OD and 69 mm width per ISO 15. SKF lists C 737 kN, C0 1860 kN, Pu 173 kN, reference speed 750 r/min and limiting speed 950 r/min, mass about 16000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4856-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4856-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4856-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×350×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4856-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×350×69 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4856-CV", "SKF NNCF 4856 CV" ], "locale_variants": {} }, { "sku": "NNCF4860-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4860 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 380, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 858, "static_load_kN": 2120, "fatigue_load_limit_kN": 196, "max_rpm": 850, "reference_speed_rpm": 700, "limiting_speed_rpm": 850, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4860 CV resolves to a 300×380×80 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 2.47 (2120 against 858 kN), and the Pu figure 196 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 700 r/min thermal reference speed and 850 r/min mechanical limiting speed. Fit practice for NNCF4860-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 858/2120 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4860-CV?", "a": "SKF NNCF 4860 CV is a double-row full-complement cylindrical roller bearing with 300 mm bore, 380 mm OD and 80 mm width per ISO 15. SKF lists C 858 kN, C0 2120 kN, Pu 196 kN, reference speed 700 r/min and limiting speed 850 r/min, mass about 22500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4860-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4860-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4860-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×380×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4860-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×380×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4860-CV", "SKF NNCF 4860 CV" ], "locale_variants": {} }, { "sku": "NNCF4864-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4864 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 400, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 897, "static_load_kN": 2280, "fatigue_load_limit_kN": 208, "max_rpm": 800, "reference_speed_rpm": 630, "limiting_speed_rpm": 800, "weight_g": 23500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4864 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 320×400×80 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 23500 g. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 320 mm seat is about 2.80 kN/mm, typical of dimension series 48 (compact heavy section); use C0 2280 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 320 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 897/2280 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4864-CV?", "a": "SKF NNCF 4864 CV is a double-row full-complement cylindrical roller bearing with 320 mm bore, 400 mm OD and 80 mm width per ISO 15. SKF lists C 897 kN, C0 2280 kN, Pu 208 kN, reference speed 630 r/min and limiting speed 800 r/min, mass about 23500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4864-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4864-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4864-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×400×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4864-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×400×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4864-CV", "SKF NNCF 4864 CV" ], "locale_variants": {} }, { "sku": "NNCF4868-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4868 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 420, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 913, "static_load_kN": 2400, "fatigue_load_limit_kN": 216, "max_rpm": 750, "reference_speed_rpm": 600, "limiting_speed_rpm": 750, "weight_g": 25000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4868 CV is a double-row full-complement cylindrical roller bearing sized 340×420×80 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF4868-CV: the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. The mass entry 25000 g covers the complete catalogue execution. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 913/2400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4868-CV?", "a": "SKF NNCF 4868 CV is a double-row full-complement cylindrical roller bearing with 340 mm bore, 420 mm OD and 80 mm width per ISO 15. SKF lists C 913 kN, C0 2400 kN, Pu 216 kN, reference speed 600 r/min and limiting speed 750 r/min, mass about 25000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4868-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4868-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4868-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×420×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4868-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×420×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4868-CV", "SKF NNCF 4868 CV" ], "locale_variants": {} }, { "sku": "NNCF4872-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4872 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 440, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 935, "static_load_kN": 2550, "fatigue_load_limit_kN": 224, "max_rpm": 700, "reference_speed_rpm": 560, "limiting_speed_rpm": 700, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 360 mm shaft, SKF lists NNCF4872-CV as double-row full-complement cylindrical roller: 440 mm OD, 80 mm wide, Pu 224 kN, the catalogue lists 560 r/min thermal reference speed and 700 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.73 (2550 against 935 kN), and the Pu figure 224 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 560 r/min thermal reference speed and 700 r/min mechanical limiting speed. Fit practice for NNCF4872-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 935/2550 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4872-CV?", "a": "SKF NNCF 4872 CV is a double-row full-complement cylindrical roller bearing with 360 mm bore, 440 mm OD and 80 mm width per ISO 15. SKF lists C 935 kN, C0 2550 kN, Pu 224 kN, reference speed 560 r/min and limiting speed 700 r/min, mass about 26500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4872-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4872-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4872-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×440×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4872-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×440×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4872-CV", "SKF NNCF 4872 CV" ], "locale_variants": {} }, { "sku": "NNCF4876-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4876 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 480, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1400, "static_load_kN": 3650, "fatigue_load_limit_kN": 315, "max_rpm": 670, "reference_speed_rpm": 530, "limiting_speed_rpm": 670, "weight_g": 45000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4876-CV is the 380 mm bore entry in the NNCF4800 range: a 380×480×100 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1400 kN / C0 3650 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.61 (3650 against 1400 kN), and the Pu figure 315 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 530 r/min thermal reference speed and 670 r/min mechanical limiting speed. Fit practice for NNCF4876-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "The 1400/3650 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4876-CV?", "a": "SKF NNCF 4876 CV is a double-row full-complement cylindrical roller bearing with 380 mm bore, 480 mm OD and 100 mm width per ISO 15. SKF lists C 1400 kN, C0 3650 kN, Pu 315 kN, reference speed 530 r/min and limiting speed 670 r/min, mass about 45000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4876-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4876-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4876-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×480×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4876-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×480×100 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4876-CV", "SKF NNCF 4876 CV" ], "locale_variants": {} }, { "sku": "NNCF4880-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4880 CV", "series": "NNCF4800-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 500, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1420, "static_load_kN": 3750, "fatigue_load_limit_kN": 325, "max_rpm": 630, "reference_speed_rpm": 500, "limiting_speed_rpm": 630, "weight_g": 46000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4880-CV is the 400 mm bore entry in the NNCF4800 range: a 400×500×100 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1420 kN / C0 3750 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 1420 kN and C0 3750 kN, size the bearing on the 400×500 mm ISO 15 envelope and check the 325 kN Pu against the equivalent-load floor; the catalogue lists 500 r/min thermal reference speed and 630 r/min mechanical limiting speed. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 400 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "The 1420/3750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4880-CV?", "a": "SKF NNCF 4880 CV is a double-row full-complement cylindrical roller bearing with 400 mm bore, 500 mm OD and 100 mm width per ISO 15. SKF lists C 1420 kN, C0 3750 kN, Pu 325 kN, reference speed 500 r/min and limiting speed 630 r/min, mass about 46000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4880-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4880-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4880-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4880-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×100 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4880-CV", "SKF NNCF 4880 CV" ], "locale_variants": {} }, { "sku": "NNCF4912-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4912 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 85, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 78.1, "static_load_kN": 137, "fatigue_load_limit_kN": 14.3, "max_rpm": 4500, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4500, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 60 mm shaft, SKF lists NNCF4912-CV as double-row full-complement cylindrical roller: 85 mm OD, 25 mm wide, Pu 14.3 kN, the catalogue lists 3,600 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.75 (137 against 78.1 kN), and the Pu figure 14.3 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Fit practice for NNCF4912-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 78.1/137 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4912-CV?", "a": "SKF NNCF 4912 CV is a double-row full-complement cylindrical roller bearing with 60 mm bore, 85 mm OD and 25 mm width per ISO 15. SKF lists C 78.1 kN, C0 137 kN, Pu 14.3 kN, reference speed 3,600 r/min and limiting speed 4,500 r/min, mass about 480 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4912-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4912-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4912-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4912-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4912-CV", "SKF NNCF 4912 CV" ], "locale_variants": {} }, { "sku": "NNCF4914-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4914 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 100, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 114, "static_load_kN": 193, "fatigue_load_limit_kN": 22.4, "max_rpm": 3800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3800, "weight_g": 770, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4914 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 70×100×30 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 770 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.69 (193 against 114 kN), and the Pu figure 22.4 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,000 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Fit practice for NNCF4914-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 100 mm raceway.", "The 114/193 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4914-CV?", "a": "SKF NNCF 4914 CV is a double-row full-complement cylindrical roller bearing with 70 mm bore, 100 mm OD and 30 mm width per ISO 15. SKF lists C 114 kN, C0 193 kN, Pu 22.4 kN, reference speed 3,000 r/min and limiting speed 3,800 r/min, mass about 770 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4914-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4914-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4914-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×100×30 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4914-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×100×30 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4914-CV", "SKF NNCF 4914 CV" ], "locale_variants": {} }, { "sku": "NNCF4916-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4916 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 110, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 121, "static_load_kN": 216, "fatigue_load_limit_kN": 25, "max_rpm": 3400, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3400, "weight_g": 870, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4916-CV is the 80 mm bore entry in the NNCF4900 range: a 80×110×30 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 121 kN / C0 216 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 80 mm seat is about 1.51 kN/mm, typical of dimension series 49 (compact heavy section); use C0 216 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 121/216 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4916-CV?", "a": "SKF NNCF 4916 CV is a double-row full-complement cylindrical roller bearing with 80 mm bore, 110 mm OD and 30 mm width per ISO 15. SKF lists C 121 kN, C0 216 kN, Pu 25 kN, reference speed 2,600 r/min and limiting speed 3,400 r/min, mass about 870 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4916-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4916-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4916-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×110×30 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4916-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×110×30 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4916-CV", "SKF NNCF 4916 CV" ], "locale_variants": {} }, { "sku": "NNCF4918-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4918 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 125, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 161, "static_load_kN": 300, "fatigue_load_limit_kN": 35.5, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4918 CV is a double-row full-complement cylindrical roller bearing sized 90×125×35 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 90 mm seat is about 1.79 kN/mm, typical of dimension series 49 (compact heavy section); use C0 300 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "The 161/300 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4918-CV?", "a": "SKF NNCF 4918 CV is a double-row full-complement cylindrical roller bearing with 90 mm bore, 125 mm OD and 35 mm width per ISO 15. SKF lists C 161 kN, C0 300 kN, Pu 35.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 1350 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4918-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4918-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4918-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×125×35 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4918-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×125×35 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4918-CV", "SKF NNCF 4918 CV" ], "locale_variants": {} }, { "sku": "NNCF4920-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4920 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 140, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 209, "static_load_kN": 400, "fatigue_load_limit_kN": 46.5, "max_rpm": 2600, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2600, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4920-CV is the 100 mm bore entry in the NNCF4900 range: a 100×140×40 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 209 kN / C0 400 kN. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 20.0 mm and the catalogue mass 1950 g; at 209 kN dynamic rating this is roughly 2.09 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 209/400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4920-CV?", "a": "SKF NNCF 4920 CV is a double-row full-complement cylindrical roller bearing with 100 mm bore, 140 mm OD and 40 mm width per ISO 15. SKF lists C 209 kN, C0 400 kN, Pu 46.5 kN, reference speed 2,000 r/min and limiting speed 2,600 r/min, mass about 1950 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4920-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4920-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4920-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×140×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4920-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×140×40 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4920-CV", "SKF NNCF 4920 CV" ], "locale_variants": {} }, { "sku": "NNCF4922-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4922 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 150, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 220, "static_load_kN": 430, "fatigue_load_limit_kN": 49, "max_rpm": 2400, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2400, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4922 CV is a double-row full-complement cylindrical roller bearing sized 110×150×40 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 20.0 mm and the catalogue mass 2100 g; at 220 kN dynamic rating this is roughly 2.00 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 220/430 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4922-CV?", "a": "SKF NNCF 4922 CV is a double-row full-complement cylindrical roller bearing with 110 mm bore, 150 mm OD and 40 mm width per ISO 15. SKF lists C 220 kN, C0 430 kN, Pu 49 kN, reference speed 1,900 r/min and limiting speed 2,400 r/min, mass about 2100 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4922-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4922-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4922-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×150×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4922-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×150×40 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4922-CV", "SKF NNCF 4922 CV" ], "locale_variants": {} }, { "sku": "NNCF4924-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4924 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 165, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 242, "static_load_kN": 480, "fatigue_load_limit_kN": 53, "max_rpm": 2200, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2200, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4924 CV resolves to a 120×165×45 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 22.5 mm and the catalogue mass 2900 g; at 242 kN dynamic rating this is roughly 2.02 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 120 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 165 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 165 mm raceway.", "The 242/480 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4924-CV?", "a": "SKF NNCF 4924 CV is a double-row full-complement cylindrical roller bearing with 120 mm bore, 165 mm OD and 45 mm width per ISO 15. SKF lists C 242 kN, C0 480 kN, Pu 53 kN, reference speed 1,700 r/min and limiting speed 2,200 r/min, mass about 2900 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4924-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4924-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4924-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×165×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4924-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×165×45 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4924-CV", "SKF NNCF 4924 CV" ], "locale_variants": {} }, { "sku": "NNCF4926-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4926 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 180, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 297, "static_load_kN": 530, "fatigue_load_limit_kN": 60, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 130 mm shaft, SKF lists NNCF4926-CV as double-row full-complement cylindrical roller: 180 mm OD, 50 mm wide, Pu 60 kN, the catalogue lists 1,600 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.78 (530 against 297 kN), and the Pu figure 60 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 297/530 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4926-CV?", "a": "SKF NNCF 4926 CV is a double-row full-complement cylindrical roller bearing with 130 mm bore, 180 mm OD and 50 mm width per ISO 15. SKF lists C 297 kN, C0 530 kN, Pu 60 kN, reference speed 1,600 r/min and limiting speed 2,000 r/min, mass about 3900 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4926-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4926-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4926-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×180×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4926-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×180×50 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4926-CV", "SKF NNCF 4926 CV" ], "locale_variants": {} }, { "sku": "NNCF4928-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4928 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 190, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 308, "static_load_kN": 570, "fatigue_load_limit_kN": 63, "max_rpm": 1900, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1900, "weight_g": 4150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4928 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 140×190×50 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 4150 g. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.85 (570 against 308 kN), and the Pu figure 63 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,500 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 308/570 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4928-CV?", "a": "SKF NNCF 4928 CV is a double-row full-complement cylindrical roller bearing with 140 mm bore, 190 mm OD and 50 mm width per ISO 15. SKF lists C 308 kN, C0 570 kN, Pu 63 kN, reference speed 1,500 r/min and limiting speed 1,900 r/min, mass about 4150 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4928-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4928-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4928-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×190×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4928-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×190×50 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4928-CV", "SKF NNCF 4928 CV" ], "locale_variants": {} }, { "sku": "NNCF4930-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4930 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 210, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 429, "static_load_kN": 830, "fatigue_load_limit_kN": 91.5, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 6550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 150 mm shaft, SKF lists NNCF4930-CV as double-row full-complement cylindrical roller: 210 mm OD, 60 mm wide, Pu 91.5 kN, the catalogue lists 1,400 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 429 kN and C0 830 kN, size the bearing on the 150×210 mm ISO 15 envelope and check the 91.5 kN Pu against the equivalent-load floor; the catalogue lists 1,400 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 429/830 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4930-CV?", "a": "SKF NNCF 4930 CV is a double-row full-complement cylindrical roller bearing with 150 mm bore, 210 mm OD and 60 mm width per ISO 15. SKF lists C 429 kN, C0 830 kN, Pu 91.5 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 6550 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4930-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4930-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4930-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×210×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4930-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×210×60 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4930-CV", "SKF NNCF 4930 CV" ], "locale_variants": {} }, { "sku": "NNCF4932-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4932 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 220, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 446, "static_load_kN": 915, "fatigue_load_limit_kN": 96.5, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 6900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4932 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 160×220×60 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 6900 g. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 446 kN and C0 915 kN, size the bearing on the 160×220 mm ISO 15 envelope and check the 96.5 kN Pu against the equivalent-load floor; the catalogue lists 1,300 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 446/915 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4932-CV?", "a": "SKF NNCF 4932 CV is a double-row full-complement cylindrical roller bearing with 160 mm bore, 220 mm OD and 60 mm width per ISO 15. SKF lists C 446 kN, C0 915 kN, Pu 96.5 kN, reference speed 1,300 r/min and limiting speed 1,600 r/min, mass about 6900 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4932-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4932-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4932-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×220×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4932-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×220×60 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4932-CV", "SKF NNCF 4932 CV" ], "locale_variants": {} }, { "sku": "NNCF4934-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4934 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 230, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 457, "static_load_kN": 950, "fatigue_load_limit_kN": 100, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 7200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4934-CV is the 170 mm bore entry in the NNCF4900 range: a 170×230×60 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 457 kN / C0 950 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 30.0 mm and the catalogue mass 7200 g; at 457 kN dynamic rating this is roughly 2.69 kN of C per millimetre of bore before application factors. Fit practice for NNCF4934-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 457/950 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4934-CV?", "a": "SKF NNCF 4934 CV is a double-row full-complement cylindrical roller bearing with 170 mm bore, 230 mm OD and 60 mm width per ISO 15. SKF lists C 457 kN, C0 950 kN, Pu 100 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 7200 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4934-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4934-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4934-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×230×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4934-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×230×60 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4934-CV", "SKF NNCF 4934 CV" ], "locale_variants": {} }, { "sku": "NNCF4936-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4936 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 250, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 594, "static_load_kN": 1220, "fatigue_load_limit_kN": 127, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4936 CV is a double-row full-complement cylindrical roller bearing sized 180×250×69 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 35.0 mm and the catalogue mass 10500 g; at 594 kN dynamic rating this is roughly 3.30 kN of C per millimetre of bore before application factors. Fit practice for NNCF4936-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 69 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 594/1220 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4936-CV?", "a": "SKF NNCF 4936 CV is a double-row full-complement cylindrical roller bearing with 180 mm bore, 250 mm OD and 69 mm width per ISO 15. SKF lists C 594 kN, C0 1220 kN, Pu 127 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 10500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4936-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4936-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4936-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×250×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4936-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×250×69 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4936-CV", "SKF NNCF 4936 CV" ], "locale_variants": {} }, { "sku": "NNCF4938-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4938 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 260, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 605, "static_load_kN": 1290, "fatigue_load_limit_kN": 132, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4938 CV resolves to a 190×260×69 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 35.0 mm and the catalogue mass 11000 g; at 605 kN dynamic rating this is roughly 3.18 kN of C per millimetre of bore before application factors. Fit practice for NNCF4938-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 69 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "The 605/1290 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4938-CV?", "a": "SKF NNCF 4938 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 260 mm OD and 69 mm width per ISO 15. SKF lists C 605 kN, C0 1290 kN, Pu 132 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 11000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4938-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4938-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4938-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4938-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4938-CV", "SKF NNCF 4938 CV" ], "locale_variants": {} }, { "sku": "NNCF4940-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4940 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 280, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 704, "static_load_kN": 1500, "fatigue_load_limit_kN": 153, "max_rpm": 1300, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1300, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 200 mm shaft, SKF lists NNCF4940-CV as double-row full-complement cylindrical roller: 280 mm OD, 80 mm wide, Pu 153 kN, the catalogue lists 1,000 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 200 mm seat is about 3.52 kN/mm, typical of dimension series 49 (compact heavy section); use C0 1500 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 704/1500 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4940-CV?", "a": "SKF NNCF 4940 CV is a double-row full-complement cylindrical roller bearing with 200 mm bore, 280 mm OD and 80 mm width per ISO 15. SKF lists C 704 kN, C0 1500 kN, Pu 153 kN, reference speed 1,000 r/min and limiting speed 1,300 r/min, mass about 15500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4940-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4940-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4940-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×280×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4940-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×280×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4940-CV", "SKF NNCF 4940 CV" ], "locale_variants": {} }, { "sku": "NNCF4944-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4944 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 300, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 737, "static_load_kN": 1600, "fatigue_load_limit_kN": 160, "max_rpm": 1200, "reference_speed_rpm": 950, "limiting_speed_rpm": 1200, "weight_g": 17000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4944-CV is the 220 mm bore entry in the NNCF4900 range: a 220×300×80 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 737 kN / C0 1600 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 737 kN and C0 1600 kN, size the bearing on the 220×300 mm ISO 15 envelope and check the 160 kN Pu against the equivalent-load floor; the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 737/1600 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4944-CV?", "a": "SKF NNCF 4944 CV is a double-row full-complement cylindrical roller bearing with 220 mm bore, 300 mm OD and 80 mm width per ISO 15. SKF lists C 737 kN, C0 1600 kN, Pu 160 kN, reference speed 950 r/min and limiting speed 1,200 r/min, mass about 17000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4944-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4944-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4944-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×300×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4944-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×300×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4944-CV", "SKF NNCF 4944 CV" ], "locale_variants": {} }, { "sku": "NNCF4948-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4948 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 320, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 781, "static_load_kN": 1760, "fatigue_load_limit_kN": 173, "max_rpm": 1100, "reference_speed_rpm": 850, "limiting_speed_rpm": 1100, "weight_g": 18500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4948 CV resolves to a 240×320×80 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 781 kN and C0 1760 kN, size the bearing on the 240×320 mm ISO 15 envelope and check the 173 kN Pu against the equivalent-load floor; the catalogue lists 850 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "The 781/1760 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4948-CV?", "a": "SKF NNCF 4948 CV is a double-row full-complement cylindrical roller bearing with 240 mm bore, 320 mm OD and 80 mm width per ISO 15. SKF lists C 781 kN, C0 1760 kN, Pu 173 kN, reference speed 850 r/min and limiting speed 1,100 r/min, mass about 18500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4948-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4948-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4948-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×320×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4948-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×320×80 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4948-CV", "SKF NNCF 4948 CV" ], "locale_variants": {} }, { "sku": "NNCF4952-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4952 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 360, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1170, "static_load_kN": 2550, "fatigue_load_limit_kN": 245, "max_rpm": 950, "reference_speed_rpm": 750, "limiting_speed_rpm": 950, "weight_g": 31500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4952 CV resolves to a 260×360×100 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.18 (2550 against 1170 kN), and the Pu figure 245 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 750 r/min thermal reference speed and 950 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1170/2550 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4952-CV?", "a": "SKF NNCF 4952 CV is a double-row full-complement cylindrical roller bearing with 260 mm bore, 360 mm OD and 100 mm width per ISO 15. SKF lists C 1170 kN, C0 2550 kN, Pu 245 kN, reference speed 750 r/min and limiting speed 950 r/min, mass about 31500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4952-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4952-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4952-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×360×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4952-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×360×100 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4952-CV", "SKF NNCF 4952 CV" ], "locale_variants": {} }, { "sku": "NNCF4956-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4956 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 380, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1210, "static_load_kN": 2700, "fatigue_load_limit_kN": 255, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 33500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 4956 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 280×380×100 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 33500 g. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCF4956-CV: the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. The mass entry 33500 g covers the complete catalogue execution. Fit practice for NNCF4956-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1210/2700 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4956-CV?", "a": "SKF NNCF 4956 CV is a double-row full-complement cylindrical roller bearing with 280 mm bore, 380 mm OD and 100 mm width per ISO 15. SKF lists C 1210 kN, C0 2700 kN, Pu 255 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 33500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4956-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4956-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4956-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×380×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4956-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×380×100 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4956-CV", "SKF NNCF 4956 CV" ], "locale_variants": {} }, { "sku": "NNCF4960-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4960 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 420, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1680, "static_load_kN": 3750, "fatigue_load_limit_kN": 355, "max_rpm": 800, "reference_speed_rpm": 670, "limiting_speed_rpm": 800, "weight_g": 52500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 4960 CV is a double-row full-complement cylindrical roller bearing sized 300×420×118 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 60.0 mm and the catalogue mass 52500 g; at 1680 kN dynamic rating this is roughly 5.60 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 300 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "The 1680/3750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4960-CV?", "a": "SKF NNCF 4960 CV is a double-row full-complement cylindrical roller bearing with 300 mm bore, 420 mm OD and 118 mm width per ISO 15. SKF lists C 1680 kN, C0 3750 kN, Pu 355 kN, reference speed 670 r/min and limiting speed 800 r/min, mass about 52500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4960-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4960-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4960-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×420×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4960-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×420×118 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4960-CV", "SKF NNCF 4960 CV" ], "locale_variants": {} }, { "sku": "NNCF4964-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4964 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 440, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1760, "static_load_kN": 4050, "fatigue_load_limit_kN": 375, "max_rpm": 750, "reference_speed_rpm": 600, "limiting_speed_rpm": 750, "weight_g": 55500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 320 mm shaft, SKF lists NNCF4964-CV as double-row full-complement cylindrical roller: 440 mm OD, 118 mm wide, Pu 375 kN, the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.30 (4050 against 1760 kN), and the Pu figure 375 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "The 1760/4050 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4964-CV?", "a": "SKF NNCF 4964 CV is a double-row full-complement cylindrical roller bearing with 320 mm bore, 440 mm OD and 118 mm width per ISO 15. SKF lists C 1760 kN, C0 4050 kN, Pu 375 kN, reference speed 600 r/min and limiting speed 750 r/min, mass about 55500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4964-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4964-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4964-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×440×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4964-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×440×118 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4964-CV", "SKF NNCF 4964 CV" ], "locale_variants": {} }, { "sku": "NNCF4968-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4968 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 460, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1790, "static_load_kN": 4250, "fatigue_load_limit_kN": 390, "max_rpm": 700, "reference_speed_rpm": 560, "limiting_speed_rpm": 700, "weight_g": 58500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4968-CV is the 340 mm bore entry in the NNCF4900 range: a 340×460×118 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1790 kN / C0 4250 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 340 mm seat is about 5.26 kN/mm, typical of dimension series 49 (compact heavy section); use C0 4250 kN for static checks such as crane hook blocks standing under load. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "The 1790/4250 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4968-CV?", "a": "SKF NNCF 4968 CV is a double-row full-complement cylindrical roller bearing with 340 mm bore, 460 mm OD and 118 mm width per ISO 15. SKF lists C 1790 kN, C0 4250 kN, Pu 390 kN, reference speed 560 r/min and limiting speed 700 r/min, mass about 58500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4968-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4968-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4968-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×460×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4968-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×460×118 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4968-CV", "SKF NNCF 4968 CV" ], "locale_variants": {} }, { "sku": "NNCF4972-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4972 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 480, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1830, "static_load_kN": 4500, "fatigue_load_limit_kN": 405, "max_rpm": 670, "reference_speed_rpm": 530, "limiting_speed_rpm": 670, "weight_g": 61500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF4972-CV is the 360 mm bore entry in the NNCF4900 range: a 360×480×118 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1830 kN / C0 4500 kN. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 1830 kN and C0 4500 kN, size the bearing on the 360×480 mm ISO 15 envelope and check the 405 kN Pu against the equivalent-load floor; the catalogue lists 530 r/min thermal reference speed and 670 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1830/4500 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4972-CV?", "a": "SKF NNCF 4972 CV is a double-row full-complement cylindrical roller bearing with 360 mm bore, 480 mm OD and 118 mm width per ISO 15. SKF lists C 1830 kN, C0 4500 kN, Pu 405 kN, reference speed 530 r/min and limiting speed 670 r/min, mass about 61500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4972-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4972-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4972-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×480×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4972-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×480×118 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4972-CV", "SKF NNCF 4972 CV" ], "locale_variants": {} }, { "sku": "NNCF4976-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4976 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 520, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2380, "static_load_kN": 5700, "fatigue_load_limit_kN": 500, "max_rpm": 630, "reference_speed_rpm": 500, "limiting_speed_rpm": 630, "weight_g": 91500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4976 CV resolves to a 380×520×140 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 70.0 mm and the catalogue mass 91500 g; at 2380 kN dynamic rating this is roughly 6.26 kN of C per millimetre of bore before application factors. Fit practice for NNCF4976-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2380/5700 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4976-CV?", "a": "SKF NNCF 4976 CV is a double-row full-complement cylindrical roller bearing with 380 mm bore, 520 mm OD and 140 mm width per ISO 15. SKF lists C 2380 kN, C0 5700 kN, Pu 500 kN, reference speed 500 r/min and limiting speed 630 r/min, mass about 91500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4976-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4976-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4976-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×520×140 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4976-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×520×140 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4976-CV", "SKF NNCF 4976 CV" ], "locale_variants": {} }, { "sku": "NNCF4980-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 4980 CV", "series": "NNCF4900-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 540, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2420, "static_load_kN": 6000, "fatigue_load_limit_kN": 520, "max_rpm": 600, "reference_speed_rpm": 480, "limiting_speed_rpm": 600, "weight_g": 95500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 4980 CV resolves to a 400×540×140 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF4980-CV: the catalogue lists 480 r/min thermal reference speed and 600 r/min mechanical limiting speed. The mass entry 95500 g covers the complete catalogue execution. Fit practice for NNCF4980-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "The 2420/6000 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF4980-CV?", "a": "SKF NNCF 4980 CV is a double-row full-complement cylindrical roller bearing with 400 mm bore, 540 mm OD and 140 mm width per ISO 15. SKF lists C 2420 kN, C0 6000 kN, Pu 520 kN, reference speed 480 r/min and limiting speed 600 r/min, mass about 95500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF4980-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF4980-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4980-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×540×140 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCL4980-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×540×140 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF4980-CV", "SKF NNCF 4980 CV" ], "locale_variants": {} }, { "sku": "NNCF5004-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5004 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 42, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 52.3, "static_load_kN": 57, "fatigue_load_limit_kN": 6.2, "max_rpm": 10000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 10000, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5004 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 20×42×30 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 200 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 52.3 kN and C0 57 kN, size the bearing on the 20×42 mm ISO 15 envelope and check the 6.2 kN Pu against the equivalent-load floor; the catalogue lists 8,500 r/min thermal reference speed and 10,000 r/min mechanical limiting speed. Fit practice for NNCF5004-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "crane sheave and hook-block hubs", "small sheave and rope-pulley supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 52.3/57 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5004-CV?", "a": "SKF NNCF 5004 CV is a double-row full-complement cylindrical roller bearing with 20 mm bore, 42 mm OD and 30 mm width per ISO 15. SKF lists C 52.3 kN, C0 57 kN, Pu 6.2 kN, reference speed 8,500 r/min and limiting speed 10,000 r/min, mass about 200 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5004-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5004-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5004-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5004 ADB-2LSV) on the same ISO 15 20×42×30 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5004-CV", "SKF NNCF 5004 CV" ], "locale_variants": {} }, { "sku": "NNCF5005-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5005 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 47, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 59.4, "static_load_kN": 71, "fatigue_load_limit_kN": 7.65, "max_rpm": 9000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 9000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 5005 CV resolves to a 25×47×30 mm double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 25 mm seat is about 2.38 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 71 kN for static checks such as crane hook blocks standing under load. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "small sheave and rope-pulley supports", "crane sheave and hook-block hubs" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 47 mm raceway.", "The 59.4/71 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5005-CV?", "a": "SKF NNCF 5005 CV is a double-row full-complement cylindrical roller bearing with 25 mm bore, 47 mm OD and 30 mm width per ISO 15. SKF lists C 59.4 kN, C0 71 kN, Pu 7.65 kN, reference speed 7,000 r/min and limiting speed 9,000 r/min, mass about 230 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5005-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5005-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5005-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5005 ADB-2LSV) on the same ISO 15 25×47×30 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5005-CV", "SKF NNCF 5005 CV" ], "locale_variants": {} }, { "sku": "NNCF5006-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5006 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 55, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 73.7, "static_load_kN": 88, "fatigue_load_limit_kN": 10, "max_rpm": 7500, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7500, "weight_g": 350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5006-CV is the 30 mm bore entry in the NNCF5000 range: a 30×55×34 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 73.7 kN / C0 88 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 73.7 kN and C0 88 kN, size the bearing on the 30×55 mm ISO 15 envelope and check the 10 kN Pu against the equivalent-load floor; the catalogue lists 6,000 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Fit practice for NNCF5006-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "hydraulic press eccentric shafts", "crane rope-sheave assemblies", "heavy gearbox low-speed shafts", "construction machinery pivot points" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 55 mm raceway.", "The 73.7/88 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5006-CV?", "a": "SKF NNCF 5006 CV is a double-row full-complement cylindrical roller bearing with 30 mm bore, 55 mm OD and 34 mm width per ISO 15. SKF lists C 73.7 kN, C0 88 kN, Pu 10 kN, reference speed 6,000 r/min and limiting speed 7,500 r/min, mass about 350 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5006-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5006-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5006-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5006 ADB-2LSV) on the same ISO 15 30×55×34 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5006-CV", "SKF NNCF 5006 CV" ], "locale_variants": {} }, { "sku": "NNCF5007-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5007 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 62, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 89.7, "static_load_kN": 112, "fatigue_load_limit_kN": 12.9, "max_rpm": 6700, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6700, "weight_g": 460, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 35 mm shaft, SKF lists NNCF5007-CV as double-row full-complement cylindrical roller: 62 mm OD, 36 mm wide, Pu 12.9 kN, the catalogue lists 5,300 r/min thermal reference speed and 6,700 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 35 mm seat is about 2.56 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 112 kN for static checks such as crane hook blocks standing under load. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "crane rope-sheave assemblies", "heavy gearbox low-speed shafts", "construction machinery pivot points", "hydraulic press eccentric shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 36 mm-wide ring and concentrates load.", "The 89.7/112 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5007-CV?", "a": "SKF NNCF 5007 CV is a double-row full-complement cylindrical roller bearing with 35 mm bore, 62 mm OD and 36 mm width per ISO 15. SKF lists C 89.7 kN, C0 112 kN, Pu 12.9 kN, reference speed 5,300 r/min and limiting speed 6,700 r/min, mass about 460 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5007-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5007-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5007-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5007 ADB-2LSV) on the same ISO 15 35×62×36 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5007-CV", "SKF NNCF 5007 CV" ], "locale_variants": {} }, { "sku": "NNCF5008-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5008 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 68, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 106, "static_load_kN": 140, "fatigue_load_limit_kN": 17, "max_rpm": 6000, "reference_speed_rpm": 4800, "limiting_speed_rpm": 6000, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5008 CV is a double-row full-complement cylindrical roller bearing sized 40×68×38 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 106 kN and C0 140 kN, size the bearing on the 40×68 mm ISO 15 envelope and check the 17 kN Pu against the equivalent-load floor; the catalogue lists 4,800 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. Fit practice for NNCF5008-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "construction machinery pivot points", "hydraulic press eccentric shafts", "crane rope-sheave assemblies", "heavy gearbox low-speed shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 38 mm-wide ring and concentrates load.", "The 106/140 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5008-CV?", "a": "SKF NNCF 5008 CV is a double-row full-complement cylindrical roller bearing with 40 mm bore, 68 mm OD and 38 mm width per ISO 15. SKF lists C 106 kN, C0 140 kN, Pu 17 kN, reference speed 4,800 r/min and limiting speed 6,000 r/min, mass about 560 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5008-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5008-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5008-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5008 ADB-2LSV) on the same ISO 15 40×68×38 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5008-CV", "SKF NNCF 5008 CV" ], "locale_variants": {} }, { "sku": "NNCF5009-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5009 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 75, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 112, "static_load_kN": 156, "fatigue_load_limit_kN": 18.3, "max_rpm": 5300, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5300, "weight_g": 710, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5009 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 45×75×40 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 710 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 45 mm seat is about 2.49 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 156 kN for static checks such as crane hook blocks standing under load. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "hydraulic press eccentric shafts", "crane rope-sheave assemblies", "heavy gearbox low-speed shafts", "construction machinery pivot points" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 112/156 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5009-CV?", "a": "SKF NNCF 5009 CV is a double-row full-complement cylindrical roller bearing with 45 mm bore, 75 mm OD and 40 mm width per ISO 15. SKF lists C 112 kN, C0 156 kN, Pu 18.3 kN, reference speed 4,300 r/min and limiting speed 5,300 r/min, mass about 710 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5009-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5009-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5009-ADB-2LSV", "equiv_brand": "SKF", "level": "full", "note": "Sealed, grease-packed counterpart (SKF NNF 5009 ADB-2LSV) on the same ISO 15 45×75×40 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5009-CV", "SKF NNCF 5009 CV" ], "locale_variants": {} }, { "sku": "NNCF5010-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5010 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 80, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 142, "static_load_kN": 196, "fatigue_load_limit_kN": 23.6, "max_rpm": 5000, "reference_speed_rpm": 4000, "limiting_speed_rpm": 5000, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5010-CV is the 50 mm bore entry in the NNCF5000 range: a 50×80×40 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 142 kN / C0 196 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.38 (196 against 142 kN), and the Pu figure 23.6 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,000 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Fit practice for NNCF5010-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "hydraulic press eccentric shafts", "crane rope-sheave assemblies", "heavy gearbox low-speed shafts", "construction machinery pivot points" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 142/196 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5010-CV?", "a": "SKF NNCF 5010 CV is a double-row full-complement cylindrical roller bearing with 50 mm bore, 80 mm OD and 40 mm width per ISO 15. SKF lists C 142 kN, C0 196 kN, Pu 23.6 kN, reference speed 4,000 r/min and limiting speed 5,000 r/min, mass about 760 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5010-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5010-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5010-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5010 ADB-2LSV) on the same ISO 15 50×80×40 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5010-CV", "SKF NNCF 5010 CV" ], "locale_variants": {} }, { "sku": "NNCF5011-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5011 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 90, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 190, "static_load_kN": 280, "fatigue_load_limit_kN": 34.5, "max_rpm": 4300, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4300, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 55 mm shaft, SKF lists NNCF5011-CV as double-row full-complement cylindrical roller: 90 mm OD, 46 mm wide, Pu 34.5 kN, the catalogue lists 3,400 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 190 kN and C0 280 kN, size the bearing on the 55×90 mm ISO 15 envelope and check the 34.5 kN Pu against the equivalent-load floor; the catalogue lists 3,400 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "crane rope-sheave assemblies", "heavy gearbox low-speed shafts", "construction machinery pivot points", "hydraulic press eccentric shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "The 190/280 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5011-CV?", "a": "SKF NNCF 5011 CV is a double-row full-complement cylindrical roller bearing with 55 mm bore, 90 mm OD and 46 mm width per ISO 15. SKF lists C 190 kN, C0 280 kN, Pu 34.5 kN, reference speed 3,400 r/min and limiting speed 4,300 r/min, mass about 1150 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5011-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5011-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5011-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5011 ADB-2LSV) on the same ISO 15 55×90×46 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5011-CV", "SKF NNCF 5011 CV" ], "locale_variants": {} }, { "sku": "NNCF5012-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5012 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 95, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 198, "static_load_kN": 300, "fatigue_load_limit_kN": 36.5, "max_rpm": 4000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4000, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5012 CV is a double-row full-complement cylindrical roller bearing sized 60×95×46 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 60 mm seat is about 3.30 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 300 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 60 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "The 198/300 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5012-CV?", "a": "SKF NNCF 5012 CV is a double-row full-complement cylindrical roller bearing with 60 mm bore, 95 mm OD and 46 mm width per ISO 15. SKF lists C 198 kN, C0 300 kN, Pu 36.5 kN, reference speed 3,400 r/min and limiting speed 4,000 r/min, mass about 1250 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5012-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5012-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5012-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5012 ADB-2LSV) on the same ISO 15 60×95×46 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5012-CV", "SKF NNCF 5012 CV" ], "locale_variants": {} }, { "sku": "NNCF5013-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5013 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 100, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 209, "static_load_kN": 325, "fatigue_load_limit_kN": 40, "max_rpm": 3800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3800, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5013 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 65×100×46 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 1300 g. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 209 kN and C0 325 kN, size the bearing on the 65×100 mm ISO 15 envelope and check the 40 kN Pu against the equivalent-load floor; the catalogue lists 3,000 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "The 209/325 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5013-CV?", "a": "SKF NNCF 5013 CV is a double-row full-complement cylindrical roller bearing with 65 mm bore, 100 mm OD and 46 mm width per ISO 15. SKF lists C 209 kN, C0 325 kN, Pu 40 kN, reference speed 3,000 r/min and limiting speed 3,800 r/min, mass about 1300 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5013-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5013-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5013-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5013 ADB-2LSV) on the same ISO 15 65×100×46 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5013-CV", "SKF NNCF 5013 CV" ], "locale_variants": {} }, { "sku": "NNCF5014-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5014 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 110, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 238, "static_load_kN": 345, "fatigue_load_limit_kN": 45, "max_rpm": 3600, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3600, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 5014 CV resolves to a 70×110×54 mm double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 70 mm seat is about 3.40 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 345 kN for static checks such as crane hook blocks standing under load. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 54 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 238/345 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5014-CV?", "a": "SKF NNCF 5014 CV is a double-row full-complement cylindrical roller bearing with 70 mm bore, 110 mm OD and 54 mm width per ISO 15. SKF lists C 238 kN, C0 345 kN, Pu 45 kN, reference speed 2,800 r/min and limiting speed 3,600 r/min, mass about 1850 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5014-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5014-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5014-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5014 ADB-2LSV) on the same ISO 15 70×110×54 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5014-CV", "SKF NNCF 5014 CV" ], "locale_variants": {} }, { "sku": "NNCF5015-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5015 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 115, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 251, "static_load_kN": 380, "fatigue_load_limit_kN": 49, "max_rpm": 3200, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3200, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5015-CV is the 75 mm bore entry in the NNCF5000 range: a 75×115×54 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 251 kN / C0 380 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 20.0 mm and the catalogue mass 1950 g; at 251 kN dynamic rating this is roughly 3.35 kN of C per millimetre of bore before application factors. Fit practice for NNCF5015-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 54 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 115 mm raceway.", "The 251/380 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5015-CV?", "a": "SKF NNCF 5015 CV is a double-row full-complement cylindrical roller bearing with 75 mm bore, 115 mm OD and 54 mm width per ISO 15. SKF lists C 251 kN, C0 380 kN, Pu 49 kN, reference speed 2,600 r/min and limiting speed 3,200 r/min, mass about 1950 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5015-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5015-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5015-ADB-2LSV", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5015 ADB-2LSV) on the same ISO 15 75×115×54 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5015-CV", "SKF NNCF 5015 CV" ], "locale_variants": {} }, { "sku": "NNCF5016-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5016 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 125, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 308, "static_load_kN": 455, "fatigue_load_limit_kN": 58.5, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 2600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 80 mm shaft, SKF lists NNCF5016-CV as double-row full-complement cylindrical roller: 125 mm OD, 60 mm wide, Pu 58.5 kN, the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF5016-CV: the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 2600 g covers the complete catalogue execution. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "The 308/455 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5016-CV?", "a": "SKF NNCF 5016 CV is a double-row full-complement cylindrical roller bearing with 80 mm bore, 125 mm OD and 60 mm width per ISO 15. SKF lists C 308 kN, C0 455 kN, Pu 58.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 2600 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5016-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5016-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5016-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5016 B-2LS) on the same ISO 15 80×125×60 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5016-CV", "SKF NNCF 5016 CV" ], "locale_variants": {} }, { "sku": "NNCF5017-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5017 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 130, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 314, "static_load_kN": 475, "fatigue_load_limit_kN": 60, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5017 CV is a double-row full-complement cylindrical roller bearing sized 85×130×60 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.51 (475 against 314 kN), and the Pu figure 60 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. Fit practice for NNCF5017-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 130 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 314/475 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5017-CV?", "a": "SKF NNCF 5017 CV is a double-row full-complement cylindrical roller bearing with 85 mm bore, 130 mm OD and 60 mm width per ISO 15. SKF lists C 314 kN, C0 475 kN, Pu 60 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 2700 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5017-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5017-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5017-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5017 B-2LS) on the same ISO 15 85×130×60 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5017-CV", "SKF NNCF 5017 CV" ], "locale_variants": {} }, { "sku": "NNCF5018-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5018 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 140, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 369, "static_load_kN": 560, "fatigue_load_limit_kN": 69.5, "max_rpm": 2800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2800, "weight_g": 3600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5018 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 90×140×67 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 3600 g. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 369 kN and C0 560 kN, size the bearing on the 90×140 mm ISO 15 envelope and check the 69.5 kN Pu against the equivalent-load floor; the catalogue lists 2,200 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 369/560 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5018-CV?", "a": "SKF NNCF 5018 CV is a double-row full-complement cylindrical roller bearing with 90 mm bore, 140 mm OD and 67 mm width per ISO 15. SKF lists C 369 kN, C0 560 kN, Pu 69.5 kN, reference speed 2,200 r/min and limiting speed 2,800 r/min, mass about 3600 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5018-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5018-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5018-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5018 B-2LS) on the same ISO 15 90×140×67 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5018-CV", "SKF NNCF 5018 CV" ], "locale_variants": {} }, { "sku": "NNCF5020-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5020 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 150, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 391, "static_load_kN": 620, "fatigue_load_limit_kN": 75, "max_rpm": 2600, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2600, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 100 mm shaft, SKF lists NNCF5020-CV as double-row full-complement cylindrical roller: 150 mm OD, 67 mm wide, Pu 75 kN, the catalogue lists 2,000 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.59 (620 against 391 kN), and the Pu figure 75 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,000 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "The 391/620 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5020-CV?", "a": "SKF NNCF 5020 CV is a double-row full-complement cylindrical roller bearing with 100 mm bore, 150 mm OD and 67 mm width per ISO 15. SKF lists C 391 kN, C0 620 kN, Pu 75 kN, reference speed 2,000 r/min and limiting speed 2,600 r/min, mass about 3950 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5020-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5020-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5020-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5020 B-2LS) on the same ISO 15 100×150×67 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5020-CV", "SKF NNCF 5020 CV" ], "locale_variants": {} }, { "sku": "NNCF5022-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5022 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 170, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 512, "static_load_kN": 800, "fatigue_load_limit_kN": 95, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 6300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5022 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 110×170×80 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 6300 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.56 (800 against 512 kN), and the Pu figure 95 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,800 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 512/800 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5022-CV?", "a": "SKF NNCF 5022 CV is a double-row full-complement cylindrical roller bearing with 110 mm bore, 170 mm OD and 80 mm width per ISO 15. SKF lists C 512 kN, C0 800 kN, Pu 95 kN, reference speed 1,800 r/min and limiting speed 2,200 r/min, mass about 6300 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5022-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5022-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5022-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5022 B-2LS) on the same ISO 15 110×170×80 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5022-CV", "SKF NNCF 5022 CV" ], "locale_variants": {} }, { "sku": "NNCF5024-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5024 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 180, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 539, "static_load_kN": 880, "fatigue_load_limit_kN": 104, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 6750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5024-CV is the 120 mm bore entry in the NNCF5000 range: a 120×180×80 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 539 kN / C0 880 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.63 (880 against 539 kN), and the Pu figure 104 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,700 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 539/880 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5024-CV?", "a": "SKF NNCF 5024 CV is a double-row full-complement cylindrical roller bearing with 120 mm bore, 180 mm OD and 80 mm width per ISO 15. SKF lists C 539 kN, C0 880 kN, Pu 104 kN, reference speed 1,700 r/min and limiting speed 2,000 r/min, mass about 6750 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5024-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5024-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5024-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5024 B-2LS) on the same ISO 15 120×180×80 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5024-CV", "SKF NNCF 5024 CV" ], "locale_variants": {} }, { "sku": "NNCF5026-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5026 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 200, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 765, "static_load_kN": 1250, "fatigue_load_limit_kN": 143, "max_rpm": 1900, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1900, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5026 CV is a double-row full-complement cylindrical roller bearing sized 130×200×95 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.63 (1250 against 765 kN), and the Pu figure 143 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,500 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 765/1250 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5026-CV?", "a": "SKF NNCF 5026 CV is a double-row full-complement cylindrical roller bearing with 130 mm bore, 200 mm OD and 95 mm width per ISO 15. SKF lists C 765 kN, C0 1250 kN, Pu 143 kN, reference speed 1,500 r/min and limiting speed 1,900 r/min, mass about 10000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5026-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5026-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5026-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5026 B-2LS) on the same ISO 15 130×200×95 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5026-CV", "SKF NNCF 5026 CV" ], "locale_variants": {} }, { "sku": "NNCF5028-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5028 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 210, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 809, "static_load_kN": 1370, "fatigue_load_limit_kN": 153, "max_rpm": 1800, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1800, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 5028 CV resolves to a 140×210×95 mm double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 140 mm seat is about 5.78 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 1370 kN for static checks such as crane hook blocks standing under load. Fit practice for NNCF5028-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 809/1370 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5028-CV?", "a": "SKF NNCF 5028 CV is a double-row full-complement cylindrical roller bearing with 140 mm bore, 210 mm OD and 95 mm width per ISO 15. SKF lists C 809 kN, C0 1370 kN, Pu 153 kN, reference speed 1,400 r/min and limiting speed 1,800 r/min, mass about 11000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5028-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5028-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5028-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5028 B-2LS) on the same ISO 15 140×210×95 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5028-CV", "SKF NNCF 5028 CV" ], "locale_variants": {} }, { "sku": "NNCF5030-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5030 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 225, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 842, "static_load_kN": 1430, "fatigue_load_limit_kN": 160, "max_rpm": 1700, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1700, "weight_g": 13500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 150 mm shaft, SKF lists NNCF5030-CV as double-row full-complement cylindrical roller: 225 mm OD, 100 mm wide, Pu 160 kN, the catalogue lists 1,300 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 37.5 mm and the catalogue mass 13500 g; at 842 kN dynamic rating this is roughly 5.61 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 150 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 225 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 225 mm raceway.", "The 842/1430 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5030-CV?", "a": "SKF NNCF 5030 CV is a double-row full-complement cylindrical roller bearing with 150 mm bore, 225 mm OD and 100 mm width per ISO 15. SKF lists C 842 kN, C0 1430 kN, Pu 160 kN, reference speed 1,300 r/min and limiting speed 1,700 r/min, mass about 13500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5030-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5030-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5030-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5030 B-2LS) on the same ISO 15 150×225×100 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5030-CV", "SKF NNCF 5030 CV" ], "locale_variants": {} }, { "sku": "NNCF5032-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5032 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 240, "B_mm": 109, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 952, "static_load_kN": 1600, "fatigue_load_limit_kN": 180, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5032 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 160×240×109 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 16000 g. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 40.0 mm and the catalogue mass 16000 g; at 952 kN dynamic rating this is roughly 5.95 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 240 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 109 mm-wide ring and concentrates load.", "The 952/1600 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5032-CV?", "a": "SKF NNCF 5032 CV is a double-row full-complement cylindrical roller bearing with 160 mm bore, 240 mm OD and 109 mm width per ISO 15. SKF lists C 952 kN, C0 1600 kN, Pu 180 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 16000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5032-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5032-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5032-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5032 B-2LS) on the same ISO 15 160×240×109 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5032-CV", "SKF NNCF 5032 CV" ], "locale_variants": {} }, { "sku": "NNCF5034-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5034 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 260, "B_mm": 122, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1230, "static_load_kN": 2120, "fatigue_load_limit_kN": 236, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5034-CV is the 170 mm bore entry in the NNCF5000 range: a 170×260×122 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1230 kN / C0 2120 kN. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 45.0 mm and the catalogue mass 23000 g; at 1230 kN dynamic rating this is roughly 7.24 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 170 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1230/2120 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5034-CV?", "a": "SKF NNCF 5034 CV is a double-row full-complement cylindrical roller bearing with 170 mm bore, 260 mm OD and 122 mm width per ISO 15. SKF lists C 1230 kN, C0 2120 kN, Pu 236 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 23000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5034-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5034-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5034-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5034 B-2LS) on the same ISO 15 170×260×122 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5034-CV", "SKF NNCF 5034 CV" ], "locale_variants": {} }, { "sku": "NNCF5036-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5036 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 280, "B_mm": 136, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1420, "static_load_kN": 2500, "fatigue_load_limit_kN": 270, "max_rpm": 1300, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1300, "weight_g": 30500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5036 CV is a double-row full-complement cylindrical roller bearing sized 180×280×136 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 50.0 mm and the catalogue mass 30500 g; at 1420 kN dynamic rating this is roughly 7.89 kN of C per millimetre of bore before application factors. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 180 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "The 1420/2500 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5036-CV?", "a": "SKF NNCF 5036 CV is a double-row full-complement cylindrical roller bearing with 180 mm bore, 280 mm OD and 136 mm width per ISO 15. SKF lists C 1420 kN, C0 2500 kN, Pu 270 kN, reference speed 1,100 r/min and limiting speed 1,300 r/min, mass about 30500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5036-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5036-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5036-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5036 B-2LS) on the same ISO 15 180×280×136 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5036-CV", "SKF NNCF 5036 CV" ], "locale_variants": {} }, { "sku": "NNCF5038-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5038 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 290, "B_mm": 136, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1470, "static_load_kN": 2600, "fatigue_load_limit_kN": 280, "max_rpm": 1300, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1300, "weight_g": 31500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 5038 CV resolves to a 190×290×136 mm double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.77 (2600 against 1470 kN), and the Pu figure 280 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,000 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 290 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1470/2600 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5038-CV?", "a": "SKF NNCF 5038 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 290 mm OD and 136 mm width per ISO 15. SKF lists C 1470 kN, C0 2600 kN, Pu 280 kN, reference speed 1,000 r/min and limiting speed 1,300 r/min, mass about 31500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5038-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5038-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5038-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5038 B-2LS) on the same ISO 15 190×290×136 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5038-CV", "SKF NNCF 5038 CV" ], "locale_variants": {} }, { "sku": "NNCF5040-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5040 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 310, "B_mm": 150, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1680, "static_load_kN": 3050, "fatigue_load_limit_kN": 320, "max_rpm": 1200, "reference_speed_rpm": 950, "limiting_speed_rpm": 1200, "weight_g": 41000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5040 CV is a double-row full-complement cylindrical roller bearing sized 200×310×150 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 1680 kN and C0 3050 kN, size the bearing on the 200×310 mm ISO 15 envelope and check the 320 kN Pu against the equivalent-load floor; the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 150 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 310 mm raceway.", "The 1680/3050 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5040-CV?", "a": "SKF NNCF 5040 CV is a double-row full-complement cylindrical roller bearing with 200 mm bore, 310 mm OD and 150 mm width per ISO 15. SKF lists C 1680 kN, C0 3050 kN, Pu 320 kN, reference speed 950 r/min and limiting speed 1,200 r/min, mass about 41000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5040-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5040-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5040-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5040 B-2LS) on the same ISO 15 200×310×150 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5040-CV", "SKF NNCF 5040 CV" ], "locale_variants": {} }, { "sku": "NNCF5044-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5044 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 340, "B_mm": 160, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2010, "static_load_kN": 3600, "fatigue_load_limit_kN": 375, "max_rpm": 1100, "reference_speed_rpm": 850, "limiting_speed_rpm": 1100, "weight_g": 52500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 220 mm shaft, SKF lists NNCF5044-CV as double-row full-complement cylindrical roller: 340 mm OD, 160 mm wide, Pu 375 kN, the catalogue lists 850 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 2010 kN and C0 3600 kN, size the bearing on the 220×340 mm ISO 15 envelope and check the 375 kN Pu against the equivalent-load floor; the catalogue lists 850 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 160 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2010/3600 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5044-CV?", "a": "SKF NNCF 5044 CV is a double-row full-complement cylindrical roller bearing with 220 mm bore, 340 mm OD and 160 mm width per ISO 15. SKF lists C 2010 kN, C0 3600 kN, Pu 375 kN, reference speed 850 r/min and limiting speed 1,100 r/min, mass about 52500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5044-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5044-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5044-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5044 B-2LS) on the same ISO 15 220×340×160 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5044-CV", "SKF NNCF 5044 CV" ], "locale_variants": {} }, { "sku": "NNCF5048-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5048 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 360, "B_mm": 160, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2120, "static_load_kN": 3900, "fatigue_load_limit_kN": 400, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 56000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5048-CV is the 240 mm bore entry in the NNCF5000 range: a 240×360×160 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 2120 kN / C0 3900 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 60.0 mm and the catalogue mass 56000 g; at 2120 kN dynamic rating this is roughly 8.83 kN of C per millimetre of bore before application factors. Fit practice for NNCF5048-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 160 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2120/3900 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5048-CV?", "a": "SKF NNCF 5048 CV is a double-row full-complement cylindrical roller bearing with 240 mm bore, 360 mm OD and 160 mm width per ISO 15. SKF lists C 2120 kN, C0 3900 kN, Pu 400 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 56000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5048-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5048-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5048-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5048 B-2LS) on the same ISO 15 240×360×160 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5048-CV", "SKF NNCF 5048 CV" ], "locale_variants": {} }, { "sku": "NNCF5052-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5052 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 400, "B_mm": 190, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2860, "static_load_kN": 5100, "fatigue_load_limit_kN": 500, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 85500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5052-CV is the 260 mm bore entry in the NNCF5000 range: a 260×400×190 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 2860 kN / C0 5100 kN. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF5052-CV: the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. The mass entry 85500 g covers the complete catalogue execution. Fit practice for NNCF5052-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 190 mm-wide ring and concentrates load.", "The 2860/5100 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5052-CV?", "a": "SKF NNCF 5052 CV is a double-row full-complement cylindrical roller bearing with 260 mm bore, 400 mm OD and 190 mm width per ISO 15. SKF lists C 2860 kN, C0 5100 kN, Pu 500 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 85500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5052-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5052-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5052-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5052 B-2LS) on the same ISO 15 260×400×190 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5052-CV", "SKF NNCF 5052 CV" ], "locale_variants": {} }, { "sku": "NNCF5056-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5056 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 420, "B_mm": 190, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2920, "static_load_kN": 5300, "fatigue_load_limit_kN": 520, "max_rpm": 850, "reference_speed_rpm": 670, "limiting_speed_rpm": 850, "weight_g": 90500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5056 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 280×420×190 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 90500 g. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCF5056-CV: the catalogue lists 670 r/min thermal reference speed and 850 r/min mechanical limiting speed. The mass entry 90500 g covers the complete catalogue execution. Mounting: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. A 280 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "The 2920/5300 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5056-CV?", "a": "SKF NNCF 5056 CV is a double-row full-complement cylindrical roller bearing with 280 mm bore, 420 mm OD and 190 mm width per ISO 15. SKF lists C 2920 kN, C0 5300 kN, Pu 520 kN, reference speed 670 r/min and limiting speed 850 r/min, mass about 90500 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5056-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5056-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNF5056-B-2LS", "equiv_brand": "SKF", "level": "partial", "note": "Sealed, grease-packed counterpart (SKF NNF 5056 B-2LS) on the same ISO 15 280×420×190 mm envelope; contact seals both sides reduce the limiting speed and catalogue ratings differ by execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5056-CV", "SKF NNCF 5056 CV" ], "locale_variants": {} }, { "sku": "NNCF5060-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5060 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 460, "B_mm": 218, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 3520, "static_load_kN": 6550, "fatigue_load_limit_kN": 600, "max_rpm": 750, "reference_speed_rpm": 600, "limiting_speed_rpm": 750, "weight_g": 130000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCF 5060 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 300×460×218 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 130000 g. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.86 (6550 against 3520 kN), and the Pu figure 600 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 218 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "The 3520/6550 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5060-CV?", "a": "SKF NNCF 5060 CV is a double-row full-complement cylindrical roller bearing with 300 mm bore, 460 mm OD and 218 mm width per ISO 15. SKF lists C 3520 kN, C0 6550 kN, Pu 600 kN, reference speed 600 r/min and limiting speed 750 r/min, mass about 130000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5060-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5060-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5060", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5060-CV", "SKF NNCF 5060 CV" ], "locale_variants": {} }, { "sku": "NNCF5064-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5064 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 480, "B_mm": 218, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 3690, "static_load_kN": 6950, "fatigue_load_limit_kN": 620, "max_rpm": 700, "reference_speed_rpm": 560, "limiting_speed_rpm": 700, "weight_g": 135000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCF 5064 CV is a double-row full-complement cylindrical roller bearing sized 320×480×218 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 320 mm seat is about 11.53 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 6950 kN for static checks such as crane hook blocks standing under load. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 3690/6950 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5064-CV?", "a": "SKF NNCF 5064 CV is a double-row full-complement cylindrical roller bearing with 320 mm bore, 480 mm OD and 218 mm width per ISO 15. SKF lists C 3690 kN, C0 6950 kN, Pu 620 kN, reference speed 560 r/min and limiting speed 700 r/min, mass about 135000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5064-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5064-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5064", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5064-CV", "SKF NNCF 5064 CV" ], "locale_variants": {} }, { "sku": "NNCF5068-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5068 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 520, "B_mm": 243, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 4400, "static_load_kN": 8300, "fatigue_load_limit_kN": 710, "max_rpm": 670, "reference_speed_rpm": 530, "limiting_speed_rpm": 670, "weight_g": 185000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 340 mm shaft, SKF lists NNCF5068-CV as double-row full-complement cylindrical roller: 520 mm OD, 243 mm wide, Pu 710 kN, the catalogue lists 530 r/min thermal reference speed and 670 r/min mechanical limiting speed. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCF5068-CV: the catalogue lists 530 r/min thermal reference speed and 670 r/min mechanical limiting speed. The mass entry 185000 g covers the complete catalogue execution. Fit practice for NNCF5068-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 4400/8300 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5068-CV?", "a": "SKF NNCF 5068 CV is a double-row full-complement cylindrical roller bearing with 340 mm bore, 520 mm OD and 243 mm width per ISO 15. SKF lists C 4400 kN, C0 8300 kN, Pu 710 kN, reference speed 530 r/min and limiting speed 670 r/min, mass about 185000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5068-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5068-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5068", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5068-CV", "SKF NNCF 5068 CV" ], "locale_variants": {} }, { "sku": "NNCF5072-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5072 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 540, "B_mm": 243, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 4180, "static_load_kN": 8650, "fatigue_load_limit_kN": 735, "max_rpm": 630, "reference_speed_rpm": 500, "limiting_speed_rpm": 630, "weight_g": 195000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 360 mm shaft, SKF lists NNCF5072-CV as double-row full-complement cylindrical roller: 540 mm OD, 243 mm wide, Pu 735 kN, the catalogue lists 500 r/min thermal reference speed and 630 r/min mechanical limiting speed. Structurally, the NNCF design has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. In arrangement terms it is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 90.0 mm and the catalogue mass 195000 g; at 4180 kN dynamic rating this is roughly 11.61 kN of C per millimetre of bore before application factors. Fit practice for NNCF5072-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 243 mm-wide ring and concentrates load.", "The 4180/8650 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5072-CV?", "a": "SKF NNCF 5072 CV is a double-row full-complement cylindrical roller bearing with 360 mm bore, 540 mm OD and 243 mm width per ISO 15. SKF lists C 4180 kN, C0 8650 kN, Pu 735 kN, reference speed 500 r/min and limiting speed 630 r/min, mass about 195000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5072-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5072-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5072", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5072-CV", "SKF NNCF 5072 CV" ], "locale_variants": {} }, { "sku": "NNCF5076-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5076 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 560, "B_mm": 243, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 4680, "static_load_kN": 9150, "fatigue_load_limit_kN": 750, "max_rpm": 600, "reference_speed_rpm": 480, "limiting_speed_rpm": 600, "weight_g": 200000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCF5076-CV is the 380 mm bore entry in the NNCF5000 range: a 380×560×243 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 4680 kN / C0 9150 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.96 (9150 against 4680 kN), and the Pu figure 750 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 480 r/min thermal reference speed and 600 r/min mechanical limiting speed. Fit practice for NNCF5076-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 243 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 560 mm raceway.", "The 4680/9150 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5076-CV?", "a": "SKF NNCF 5076 CV is a double-row full-complement cylindrical roller bearing with 380 mm bore, 560 mm OD and 243 mm width per ISO 15. SKF lists C 4680 kN, C0 9150 kN, Pu 750 kN, reference speed 480 r/min and limiting speed 600 r/min, mass about 200000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5076-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5076-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5076", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5076-CV", "SKF NNCF 5076 CV" ], "locale_variants": {} }, { "sku": "NNCF5080-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCF 5080 CV", "series": "NNCF5000-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 600, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 5500, "static_load_kN": 11000, "fatigue_load_limit_kN": 900, "max_rpm": 560, "reference_speed_rpm": 450, "limiting_speed_rpm": 560, "weight_g": 270000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCF 5080 CV resolves to a 400×600×272 mm double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. The NNCF configuration means a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes; functionally the bearing is one-direction locating: the retained outer ring guides the shaft axially in one direction. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 5500 kN and C0 11000 kN, size the bearing on the 400×600 mm ISO 15 envelope and check the 900 kN Pu against the equivalent-load floor; the catalogue lists 450 r/min thermal reference speed and 560 r/min mechanical limiting speed. Assembly note: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 600 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 600 mm raceway.", "The 5500/11000 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCF5080-CV?", "a": "SKF NNCF 5080 CV is a double-row full-complement cylindrical roller bearing with 400 mm bore, 600 mm OD and 272 mm width per ISO 15. SKF lists C 5500 kN, C0 11000 kN, Pu 900 kN, reference speed 450 r/min and limiting speed 560 r/min, mass about 270000 g." }, { "q": "What does the NNCF designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes." }, { "q": "Can NNCF5080-CV take axial load and locate the shaft?", "a": "In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust." }, { "q": "How does NNCF5080-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNCF5080", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCF5080-CV", "SKF NNCF 5080 CV" ], "locale_variants": {} }, { "sku": "NNCL4830-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4830 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 190, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 255, "static_load_kN": 585, "fatigue_load_limit_kN": 60, "max_rpm": 1800, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1800, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4830-CV is the 150 mm bore entry in the NNCL4800 range: a 150×190×40 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 255 kN / C0 585 kN. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 255 kN and C0 585 kN, size the bearing on the 150×190 mm ISO 15 envelope and check the 60 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 1,800 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 255/585 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4830-CV?", "a": "SKF NNCL 4830 CV is a double-row full-complement cylindrical roller bearing with 150 mm bore, 190 mm OD and 40 mm width per ISO 15. SKF lists C 255 kN, C0 585 kN, Pu 60 kN, reference speed 1,500 r/min and limiting speed 1,800 r/min, mass about 2700 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4830-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4830-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4830-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×190×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4830-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×190×40 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4830-CV", "SKF NNCL 4830 CV" ], "locale_variants": {} }, { "sku": "NNCL4832-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4832 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 200, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 260, "static_load_kN": 610, "fatigue_load_limit_kN": 62, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4832 CV is a double-row full-complement cylindrical roller bearing sized 160×200×40 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 20.0 mm and the catalogue mass 2900 g; at 260 kN dynamic rating this is roughly 1.63 kN of C per millimetre of bore before application factors. Fit practice for NNCL4832-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 260/610 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4832-CV?", "a": "SKF NNCL 4832 CV is a double-row full-complement cylindrical roller bearing with 160 mm bore, 200 mm OD and 40 mm width per ISO 15. SKF lists C 260 kN, C0 610 kN, Pu 62 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 2900 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4832-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4832-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4832-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×200×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4832-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×200×40 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4832-CV", "SKF NNCL 4832 CV" ], "locale_variants": {} }, { "sku": "NNCL4834-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4834 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 215, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 286, "static_load_kN": 655, "fatigue_load_limit_kN": 65.5, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4834 CV resolves to a 170×215×45 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 22.5 mm and the catalogue mass 3900 g; at 286 kN dynamic rating this is roughly 1.68 kN of C per millimetre of bore before application factors. Fit practice for NNCL4834-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 286/655 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4834-CV?", "a": "SKF NNCL 4834 CV is a double-row full-complement cylindrical roller bearing with 170 mm bore, 215 mm OD and 45 mm width per ISO 15. SKF lists C 286 kN, C0 655 kN, Pu 65.5 kN, reference speed 1,300 r/min and limiting speed 1,600 r/min, mass about 3900 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4834-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4834-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4834-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×215×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4834-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×215×45 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4834-CV", "SKF NNCL 4834 CV" ], "locale_variants": {} }, { "sku": "NNCL4836-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4836 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 225, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 297, "static_load_kN": 695, "fatigue_load_limit_kN": 69.5, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 180 mm shaft, SKF lists NNCL4836-CV as double-row full-complement cylindrical roller: 225 mm OD, 45 mm wide, Pu 69.5 kN, the catalogue lists 1,200 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 22.5 mm and the catalogue mass 4100 g; at 297 kN dynamic rating this is roughly 1.65 kN of C per millimetre of bore before application factors. Fit practice for NNCL4836-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 225 mm raceway.", "The 297/695 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4836-CV?", "a": "SKF NNCL 4836 CV is a double-row full-complement cylindrical roller bearing with 180 mm bore, 225 mm OD and 45 mm width per ISO 15. SKF lists C 297 kN, C0 695 kN, Pu 69.5 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 4100 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4836-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4836-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4836-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×225×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4836-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×225×45 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4836-CV", "SKF NNCL 4836 CV" ], "locale_variants": {} }, { "sku": "NNCL4838-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4838 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 240, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 358, "static_load_kN": 750, "fatigue_load_limit_kN": 76.5, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 5300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4838 CV is a double-row full-complement cylindrical roller bearing sized 190×240×50 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 25.0 mm and the catalogue mass 5300 g; at 358 kN dynamic rating this is roughly 1.88 kN of C per millimetre of bore before application factors. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "The 358/750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4838-CV?", "a": "SKF NNCL 4838 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 358 kN, C0 750 kN, Pu 76.5 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 5300 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4838-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4838-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4838-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×240×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4838-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×240×50 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4838-CV", "SKF NNCL 4838 CV" ], "locale_variants": {} }, { "sku": "NNCL4840-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4840 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 250, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 369, "static_load_kN": 800, "fatigue_load_limit_kN": 80, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 5700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4840-CV is the 200 mm bore entry in the NNCL4800 range: a 200×250×50 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 369 kN / C0 800 kN. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Speed planning for NNCL4840-CV: the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. The mass entry 5700 g covers the complete catalogue execution. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 369/800 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4840-CV?", "a": "SKF NNCL 4840 CV is a double-row full-complement cylindrical roller bearing with 200 mm bore, 250 mm OD and 50 mm width per ISO 15. SKF lists C 369 kN, C0 800 kN, Pu 80 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 5700 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4840-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4840-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4840-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×250×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4840-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×250×50 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4840-CV", "SKF NNCL 4840 CV" ], "locale_variants": {} }, { "sku": "NNCL4844-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4844 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 270, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 380, "static_load_kN": 865, "fatigue_load_limit_kN": 85, "max_rpm": 1200, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1200, "weight_g": 6200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4844 CV resolves to a 220×270×50 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 380 kN and C0 865 kN, size the bearing on the 220×270 mm ISO 15 envelope and check the 85 kN Pu against the equivalent-load floor; the catalogue lists 1,000 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 380/865 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4844-CV?", "a": "SKF NNCL 4844 CV is a double-row full-complement cylindrical roller bearing with 220 mm bore, 270 mm OD and 50 mm width per ISO 15. SKF lists C 380 kN, C0 865 kN, Pu 85 kN, reference speed 1,000 r/min and limiting speed 1,200 r/min, mass about 6200 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4844-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4844-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4844-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×270×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4844-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×270×50 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4844-CV", "SKF NNCL 4844 CV" ], "locale_variants": {} }, { "sku": "NNCL4848-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4848 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 300, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 539, "static_load_kN": 1290, "fatigue_load_limit_kN": 125, "max_rpm": 1100, "reference_speed_rpm": 900, "limiting_speed_rpm": 1100, "weight_g": 9800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4848 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 240×300×60 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 9800 g. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 30.0 mm and the catalogue mass 9800 g; at 539 kN dynamic rating this is roughly 2.25 kN of C per millimetre of bore before application factors. Fit practice for NNCL4848-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 539/1290 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4848-CV?", "a": "SKF NNCL 4848 CV is a double-row full-complement cylindrical roller bearing with 240 mm bore, 300 mm OD and 60 mm width per ISO 15. SKF lists C 539 kN, C0 1290 kN, Pu 125 kN, reference speed 900 r/min and limiting speed 1,100 r/min, mass about 9800 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4848-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4848-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4848-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×300×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4848-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×300×60 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4848-CV", "SKF NNCL 4848 CV" ], "locale_variants": {} }, { "sku": "NNCL4852-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4852 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 320, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 561, "static_load_kN": 1400, "fatigue_load_limit_kN": 132, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4852 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 260×320×60 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 10500 g. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 260 mm seat is about 2.16 kN/mm, typical of dimension series 48 (compact heavy section); use C0 1400 kN for static checks such as crane hook blocks standing under load. Fit practice for NNCL4852-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 561/1400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4852-CV?", "a": "SKF NNCL 4852 CV is a double-row full-complement cylindrical roller bearing with 260 mm bore, 320 mm OD and 60 mm width per ISO 15. SKF lists C 561 kN, C0 1400 kN, Pu 132 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 10500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4852-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4852-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4852-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×320×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4852-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×320×60 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4852-CV", "SKF NNCL 4852 CV" ], "locale_variants": {} }, { "sku": "NNCL4856-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4856 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 350, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 737, "static_load_kN": 1860, "fatigue_load_limit_kN": 173, "max_rpm": 950, "reference_speed_rpm": 750, "limiting_speed_rpm": 950, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4856 CV is a double-row full-complement cylindrical roller bearing sized 280×350×69 mm — a dimension series 48 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Speed planning for NNCL4856-CV: the catalogue lists 750 r/min thermal reference speed and 950 r/min mechanical limiting speed. The mass entry 15500 g covers the complete catalogue execution. Fit practice for NNCL4856-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 350 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 350 mm raceway.", "The 737/1860 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4856-CV?", "a": "SKF NNCL 4856 CV is a double-row full-complement cylindrical roller bearing with 280 mm bore, 350 mm OD and 69 mm width per ISO 15. SKF lists C 737 kN, C0 1860 kN, Pu 173 kN, reference speed 750 r/min and limiting speed 950 r/min, mass about 15500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4856-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4856-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4856-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×350×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4856-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×350×69 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4856-CV", "SKF NNCL 4856 CV" ], "locale_variants": {} }, { "sku": "NNCL4860-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4860 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 380, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 858, "static_load_kN": 2120, "fatigue_load_limit_kN": 196, "max_rpm": 850, "reference_speed_rpm": 700, "limiting_speed_rpm": 850, "weight_g": 22000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 300 mm shaft, SKF lists NNCL4860-CV as double-row full-complement cylindrical roller: 380 mm OD, 80 mm wide, Pu 196 kN, the catalogue lists 700 r/min thermal reference speed and 850 r/min mechanical limiting speed. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 2.47 (2120 against 858 kN), and the Pu figure 196 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 700 r/min thermal reference speed and 850 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "The 858/2120 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4860-CV?", "a": "SKF NNCL 4860 CV is a double-row full-complement cylindrical roller bearing with 300 mm bore, 380 mm OD and 80 mm width per ISO 15. SKF lists C 858 kN, C0 2120 kN, Pu 196 kN, reference speed 700 r/min and limiting speed 850 r/min, mass about 22000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4860-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4860-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4860-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×380×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4860-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×380×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4860-CV", "SKF NNCL 4860 CV" ], "locale_variants": {} }, { "sku": "NNCL4864-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4864 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 400, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 897, "static_load_kN": 2280, "fatigue_load_limit_kN": 208, "max_rpm": 800, "reference_speed_rpm": 630, "limiting_speed_rpm": 800, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4864-CV is the 320 mm bore entry in the NNCL4800 range: a 320×400×80 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 897 kN / C0 2280 kN. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.54 (2280 against 897 kN), and the Pu figure 208 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 630 r/min thermal reference speed and 800 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 897/2280 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4864-CV?", "a": "SKF NNCL 4864 CV is a double-row full-complement cylindrical roller bearing with 320 mm bore, 400 mm OD and 80 mm width per ISO 15. SKF lists C 897 kN, C0 2280 kN, Pu 208 kN, reference speed 630 r/min and limiting speed 800 r/min, mass about 23000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4864-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4864-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4864-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×400×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4864-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×400×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4864-CV", "SKF NNCL 4864 CV" ], "locale_variants": {} }, { "sku": "NNCL4868-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4868 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 420, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 913, "static_load_kN": 2400, "fatigue_load_limit_kN": 216, "max_rpm": 750, "reference_speed_rpm": 600, "limiting_speed_rpm": 750, "weight_g": 25500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4868 CV resolves to a 340×420×80 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCL4868-CV: the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. The mass entry 25500 g covers the complete catalogue execution. Fit practice for NNCL4868-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 913/2400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4868-CV?", "a": "SKF NNCL 4868 CV is a double-row full-complement cylindrical roller bearing with 340 mm bore, 420 mm OD and 80 mm width per ISO 15. SKF lists C 913 kN, C0 2400 kN, Pu 216 kN, reference speed 600 r/min and limiting speed 750 r/min, mass about 25500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4868-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4868-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4868-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×420×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4868-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×420×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4868-CV", "SKF NNCL 4868 CV" ], "locale_variants": {} }, { "sku": "NNCL4872-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4872 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 440, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 935, "static_load_kN": 2550, "fatigue_load_limit_kN": 224, "max_rpm": 700, "reference_speed_rpm": 560, "limiting_speed_rpm": 700, "weight_g": 26000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4872 CV resolves to a 360×440×80 mm double-row full-complement cylindrical roller bearing (dimension series 48 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 40.0 mm and the catalogue mass 26000 g; at 935 kN dynamic rating this is roughly 2.60 kN of C per millimetre of bore before application factors. Fit practice for NNCL4872-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 440 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 935/2550 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4872-CV?", "a": "SKF NNCL 4872 CV is a double-row full-complement cylindrical roller bearing with 360 mm bore, 440 mm OD and 80 mm width per ISO 15. SKF lists C 935 kN, C0 2550 kN, Pu 224 kN, reference speed 560 r/min and limiting speed 700 r/min, mass about 26000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4872-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4872-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4872-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×440×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4872-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×440×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4872-CV", "SKF NNCL 4872 CV" ], "locale_variants": {} }, { "sku": "NNCL4876-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4876 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 480, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1400, "static_load_kN": 3650, "fatigue_load_limit_kN": 315, "max_rpm": 670, "reference_speed_rpm": 530, "limiting_speed_rpm": 670, "weight_g": 44000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4876 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 380×480×100 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 44000 g. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. The radial section height is 50.0 mm and the catalogue mass 44000 g; at 1400 kN dynamic rating this is roughly 3.68 kN of C per millimetre of bore before application factors. Fit practice for NNCL4876-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "The 1400/3650 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4876-CV?", "a": "SKF NNCL 4876 CV is a double-row full-complement cylindrical roller bearing with 380 mm bore, 480 mm OD and 100 mm width per ISO 15. SKF lists C 1400 kN, C0 3650 kN, Pu 315 kN, reference speed 530 r/min and limiting speed 670 r/min, mass about 44000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4876-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4876-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4876-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×480×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4876-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×480×100 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4876-CV", "SKF NNCL 4876 CV" ], "locale_variants": {} }, { "sku": "NNCL4880-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4880 CV", "series": "NNCL4800-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 500, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1420, "static_load_kN": 3750, "fatigue_load_limit_kN": 325, "max_rpm": 630, "reference_speed_rpm": 500, "limiting_speed_rpm": 630, "weight_g": 46000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4880 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 400×500×100 mm envelope, dimension series 48 (compact heavy section), with catalogue mass 46000 g. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 1420 kN and C0 3750 kN, size the bearing on the 400×500 mm ISO 15 envelope and check the 325 kN Pu against the equivalent-load floor; the catalogue lists 500 r/min thermal reference speed and 630 r/min mechanical limiting speed. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 400 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "The 1420/3750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4880-CV?", "a": "SKF NNCL 4880 CV is a double-row full-complement cylindrical roller bearing with 400 mm bore, 500 mm OD and 100 mm width per ISO 15. SKF lists C 1420 kN, C0 3750 kN, Pu 325 kN, reference speed 500 r/min and limiting speed 630 r/min, mass about 46000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4880-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4880-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4880-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4880-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×100 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4880-CV", "SKF NNCL 4880 CV" ], "locale_variants": {} }, { "sku": "NNCL4912-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4912 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 85, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 78.1, "static_load_kN": 137, "fatigue_load_limit_kN": 14.3, "max_rpm": 4500, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4500, "weight_g": 470, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4912 CV resolves to a 60×85×25 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.75 (137 against 78.1 kN), and the Pu figure 14.3 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Fit practice for NNCL4912-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 78.1/137 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4912-CV?", "a": "SKF NNCL 4912 CV is a double-row full-complement cylindrical roller bearing with 60 mm bore, 85 mm OD and 25 mm width per ISO 15. SKF lists C 78.1 kN, C0 137 kN, Pu 14.3 kN, reference speed 3,600 r/min and limiting speed 4,500 r/min, mass about 470 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4912-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4912-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4912-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4912-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4912-CV", "SKF NNCL 4912 CV" ], "locale_variants": {} }, { "sku": "NNCL4914-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4914 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 100, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 114, "static_load_kN": 193, "fatigue_load_limit_kN": 22.4, "max_rpm": 3800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3800, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 70 mm shaft, SKF lists NNCL4914-CV as double-row full-complement cylindrical roller: 100 mm OD, 30 mm wide, Pu 22.4 kN, the catalogue lists 3,000 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 70 mm seat is about 1.63 kN/mm, typical of dimension series 49 (compact heavy section); use C0 193 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums", "offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 30 mm-wide ring and concentrates load.", "The 114/193 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4914-CV?", "a": "SKF NNCL 4914 CV is a double-row full-complement cylindrical roller bearing with 70 mm bore, 100 mm OD and 30 mm width per ISO 15. SKF lists C 114 kN, C0 193 kN, Pu 22.4 kN, reference speed 3,000 r/min and limiting speed 3,800 r/min, mass about 750 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4914-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4914-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4914-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×100×30 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4914-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×100×30 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4914-CV", "SKF NNCL 4914 CV" ], "locale_variants": {} }, { "sku": "NNCL4916-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4916 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 110, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 121, "static_load_kN": 216, "fatigue_load_limit_kN": 25, "max_rpm": 3400, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3400, "weight_g": 850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4916 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 80×110×30 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 850 g. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 80 mm seat is about 1.51 kN/mm, typical of dimension series 49 (compact heavy section); use C0 216 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 121/216 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4916-CV?", "a": "SKF NNCL 4916 CV is a double-row full-complement cylindrical roller bearing with 80 mm bore, 110 mm OD and 30 mm width per ISO 15. SKF lists C 121 kN, C0 216 kN, Pu 25 kN, reference speed 2,600 r/min and limiting speed 3,400 r/min, mass about 850 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4916-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4916-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4916-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×110×30 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4916-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×110×30 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4916-CV", "SKF NNCL 4916 CV" ], "locale_variants": {} }, { "sku": "NNCL4918-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4918 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 125, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 161, "static_load_kN": 300, "fatigue_load_limit_kN": 35.5, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4918-CV is the 90 mm bore entry in the NNCL4900 range: a 90×125×35 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 161 kN / C0 300 kN. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 90 mm seat is about 1.79 kN/mm, typical of dimension series 49 (compact heavy section); use C0 300 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "The 161/300 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4918-CV?", "a": "SKF NNCL 4918 CV is a double-row full-complement cylindrical roller bearing with 90 mm bore, 125 mm OD and 35 mm width per ISO 15. SKF lists C 161 kN, C0 300 kN, Pu 35.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 1300 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4918-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4918-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4918-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×125×35 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4918-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×125×35 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4918-CV", "SKF NNCL 4918 CV" ], "locale_variants": {} }, { "sku": "NNCL4920-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4920 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 140, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 209, "static_load_kN": 400, "fatigue_load_limit_kN": 46.5, "max_rpm": 2600, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2600, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4920 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 100×140×40 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 1900 g. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 209 kN and C0 400 kN, size the bearing on the 100×140 mm ISO 15 envelope and check the 46.5 kN Pu against the equivalent-load floor; the catalogue lists 2,000 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives", "large crane and winch drums" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 209/400 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4920-CV?", "a": "SKF NNCL 4920 CV is a double-row full-complement cylindrical roller bearing with 100 mm bore, 140 mm OD and 40 mm width per ISO 15. SKF lists C 209 kN, C0 400 kN, Pu 46.5 kN, reference speed 2,000 r/min and limiting speed 2,600 r/min, mass about 1900 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4920-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4920-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4920-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×140×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4920-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×140×40 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4920-CV", "SKF NNCL 4920 CV" ], "locale_variants": {} }, { "sku": "NNCL4922-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4922 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 150, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 220, "static_load_kN": 430, "fatigue_load_limit_kN": 49, "max_rpm": 2400, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2400, "weight_g": 2100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4922-CV is the 110 mm bore entry in the NNCL4900 range: a 110×150×40 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 220 kN / C0 430 kN. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 220 kN and C0 430 kN, size the bearing on the 110×150 mm ISO 15 envelope and check the 49 kN Pu against the equivalent-load floor; the catalogue lists 1,900 r/min thermal reference speed and 2,400 r/min mechanical limiting speed. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large crane and winch drums", "offshore crane sheaves", "heavy material-handling rope pulleys", "rolling-mill and caster drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 220/430 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4922-CV?", "a": "SKF NNCL 4922 CV is a double-row full-complement cylindrical roller bearing with 110 mm bore, 150 mm OD and 40 mm width per ISO 15. SKF lists C 220 kN, C0 430 kN, Pu 49 kN, reference speed 1,900 r/min and limiting speed 2,400 r/min, mass about 2100 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4922-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4922-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4922-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×150×40 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4922-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×150×40 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4922-CV", "SKF NNCL 4922 CV" ], "locale_variants": {} }, { "sku": "NNCL4924-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4924 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 165, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 242, "static_load_kN": 480, "fatigue_load_limit_kN": 53, "max_rpm": 2200, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2200, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4924 CV is a double-row full-complement cylindrical roller bearing sized 120×165×45 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.98 (480 against 242 kN), and the Pu figure 53 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,700 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 165 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "The 242/480 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4924-CV?", "a": "SKF NNCL 4924 CV is a double-row full-complement cylindrical roller bearing with 120 mm bore, 165 mm OD and 45 mm width per ISO 15. SKF lists C 242 kN, C0 480 kN, Pu 53 kN, reference speed 1,700 r/min and limiting speed 2,200 r/min, mass about 2850 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4924-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4924-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4924-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×165×45 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4924-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×165×45 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4924-CV", "SKF NNCL 4924 CV" ], "locale_variants": {} }, { "sku": "NNCL4926-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4926 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 180, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 297, "static_load_kN": 530, "fatigue_load_limit_kN": 60, "max_rpm": 2000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2000, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4926 CV resolves to a 130×180×50 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 1.78 (530 against 297 kN), and the Pu figure 60 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 297/530 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4926-CV?", "a": "SKF NNCL 4926 CV is a double-row full-complement cylindrical roller bearing with 130 mm bore, 180 mm OD and 50 mm width per ISO 15. SKF lists C 297 kN, C0 530 kN, Pu 60 kN, reference speed 1,600 r/min and limiting speed 2,000 r/min, mass about 3800 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4926-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4926-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4926-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×180×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4926-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×180×50 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4926-CV", "SKF NNCL 4926 CV" ], "locale_variants": {} }, { "sku": "NNCL4928-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4928 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 190, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 308, "static_load_kN": 570, "fatigue_load_limit_kN": 63, "max_rpm": 1900, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1900, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 140 mm shaft, SKF lists NNCL4928-CV as double-row full-complement cylindrical roller: 190 mm OD, 50 mm wide, Pu 63 kN, the catalogue lists 1,500 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.85 (570 against 308 kN), and the Pu figure 63 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,500 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 308/570 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4928-CV?", "a": "SKF NNCL 4928 CV is a double-row full-complement cylindrical roller bearing with 140 mm bore, 190 mm OD and 50 mm width per ISO 15. SKF lists C 308 kN, C0 570 kN, Pu 63 kN, reference speed 1,500 r/min and limiting speed 1,900 r/min, mass about 4100 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4928-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4928-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4928-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×190×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4928-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×190×50 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4928-CV", "SKF NNCL 4928 CV" ], "locale_variants": {} }, { "sku": "NNCL4930-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4930 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 210, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 429, "static_load_kN": 830, "fatigue_load_limit_kN": 91.5, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4930 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 150×210×60 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 6450 g. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNCL4930-CV: the catalogue lists 1,400 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. The mass entry 6450 g covers the complete catalogue execution. Fit practice for NNCL4930-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 429/830 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4930-CV?", "a": "SKF NNCL 4930 CV is a double-row full-complement cylindrical roller bearing with 150 mm bore, 210 mm OD and 60 mm width per ISO 15. SKF lists C 429 kN, C0 830 kN, Pu 91.5 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 6450 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4930-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4930-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4930-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×210×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4930-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×210×60 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4930-CV", "SKF NNCL 4930 CV" ], "locale_variants": {} }, { "sku": "NNCL4932-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4932 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 220, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 446, "static_load_kN": 915, "fatigue_load_limit_kN": 96.5, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 6800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4932-CV is the 160 mm bore entry in the NNCL4900 range: a 160×220×60 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 446 kN / C0 915 kN. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCL4932-CV: the catalogue lists 1,300 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. The mass entry 6800 g covers the complete catalogue execution. Fit practice for NNCL4932-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 446/915 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4932-CV?", "a": "SKF NNCL 4932 CV is a double-row full-complement cylindrical roller bearing with 160 mm bore, 220 mm OD and 60 mm width per ISO 15. SKF lists C 446 kN, C0 915 kN, Pu 96.5 kN, reference speed 1,300 r/min and limiting speed 1,600 r/min, mass about 6800 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4932-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4932-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4932-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×220×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4932-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×220×60 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4932-CV", "SKF NNCL 4932 CV" ], "locale_variants": {} }, { "sku": "NNCL4934-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4934 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 230, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 457, "static_load_kN": 950, "fatigue_load_limit_kN": 100, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 7100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4934 CV is a double-row full-complement cylindrical roller bearing sized 170×230×60 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 457 kN and C0 950 kN, size the bearing on the 170×230 mm ISO 15 envelope and check the 100 kN Pu against the equivalent-load floor; the catalogue lists 1,200 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 170 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 457/950 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4934-CV?", "a": "SKF NNCL 4934 CV is a double-row full-complement cylindrical roller bearing with 170 mm bore, 230 mm OD and 60 mm width per ISO 15. SKF lists C 457 kN, C0 950 kN, Pu 100 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 7100 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4934-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4934-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4934-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×230×60 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4934-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×230×60 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4934-CV", "SKF NNCL 4934 CV" ], "locale_variants": {} }, { "sku": "NNCL4936-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4936 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 250, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 594, "static_load_kN": 1220, "fatigue_load_limit_kN": 127, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4936 CV resolves to a 180×250×69 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. With C 594 kN and C0 1220 kN, size the bearing on the 180×250 mm ISO 15 envelope and check the 127 kN Pu against the equivalent-load floor; the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 180 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 594/1220 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4936-CV?", "a": "SKF NNCL 4936 CV is a double-row full-complement cylindrical roller bearing with 180 mm bore, 250 mm OD and 69 mm width per ISO 15. SKF lists C 594 kN, C0 1220 kN, Pu 127 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 10500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4936-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4936-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4936-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×250×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4936-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×250×69 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4936-CV", "SKF NNCL 4936 CV" ], "locale_variants": {} }, { "sku": "NNCL4938-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4938 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 260, "B_mm": 69, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 605, "static_load_kN": 1290, "fatigue_load_limit_kN": 132, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 190 mm shaft, SKF lists NNCL4938-CV as double-row full-complement cylindrical roller: 260 mm OD, 69 mm wide, Pu 132 kN, the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The radial section height is 35.0 mm and the catalogue mass 11000 g; at 605 kN dynamic rating this is roughly 3.18 kN of C per millimetre of bore before application factors. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 69 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "The 605/1290 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4938-CV?", "a": "SKF NNCL 4938 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 260 mm OD and 69 mm width per ISO 15. SKF lists C 605 kN, C0 1290 kN, Pu 132 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 11000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4938-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4938-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4938-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4938-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4938-CV", "SKF NNCL 4938 CV" ], "locale_variants": {} }, { "sku": "NNCL4940-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4940 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 280, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 704, "static_load_kN": 1500, "fatigue_load_limit_kN": 153, "max_rpm": 1300, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1300, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4940 CV resolves to a 200×280×80 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 200 mm seat is about 3.52 kN/mm, typical of dimension series 49 (compact heavy section); use C0 1500 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 704/1500 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4940-CV?", "a": "SKF NNCL 4940 CV is a double-row full-complement cylindrical roller bearing with 200 mm bore, 280 mm OD and 80 mm width per ISO 15. SKF lists C 704 kN, C0 1500 kN, Pu 153 kN, reference speed 1,000 r/min and limiting speed 1,300 r/min, mass about 15500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4940-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4940-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4940-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×280×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4940-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×280×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4940-CV", "SKF NNCL 4940 CV" ], "locale_variants": {} }, { "sku": "NNCL4944-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4944 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 300, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 737, "static_load_kN": 1600, "fatigue_load_limit_kN": 160, "max_rpm": 1200, "reference_speed_rpm": 950, "limiting_speed_rpm": 1200, "weight_g": 17000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4944 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 220×300×80 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 17000 g. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Speed planning for NNCL4944-CV: the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. The mass entry 17000 g covers the complete catalogue execution. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 300 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 737/1600 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4944-CV?", "a": "SKF NNCL 4944 CV is a double-row full-complement cylindrical roller bearing with 220 mm bore, 300 mm OD and 80 mm width per ISO 15. SKF lists C 737 kN, C0 1600 kN, Pu 160 kN, reference speed 950 r/min and limiting speed 1,200 r/min, mass about 17000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4944-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4944-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4944-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×300×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4944-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×300×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4944-CV", "SKF NNCL 4944 CV" ], "locale_variants": {} }, { "sku": "NNCL4948-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4948 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 320, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 781, "static_load_kN": 1760, "fatigue_load_limit_kN": 173, "max_rpm": 1100, "reference_speed_rpm": 850, "limiting_speed_rpm": 1100, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4948 CV is a double-row full-complement cylindrical roller bearing sized 240×320×80 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNCL4948-CV: the catalogue lists 850 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. The mass entry 18000 g covers the complete catalogue execution. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "large offshore winch and hook blocks", "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "The 781/1760 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4948-CV?", "a": "SKF NNCL 4948 CV is a double-row full-complement cylindrical roller bearing with 240 mm bore, 320 mm OD and 80 mm width per ISO 15. SKF lists C 781 kN, C0 1760 kN, Pu 173 kN, reference speed 850 r/min and limiting speed 1,100 r/min, mass about 18000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4948-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4948-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4948-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×320×80 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4948-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×320×80 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4948-CV", "SKF NNCL 4948 CV" ], "locale_variants": {} }, { "sku": "NNCL4952-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4952 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 360, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1170, "static_load_kN": 2550, "fatigue_load_limit_kN": 245, "max_rpm": 950, "reference_speed_rpm": 750, "limiting_speed_rpm": 950, "weight_g": 31000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 260 mm shaft, SKF lists NNCL4952-CV as double-row full-complement cylindrical roller: 360 mm OD, 100 mm wide, Pu 245 kN, the catalogue lists 750 r/min thermal reference speed and 950 r/min mechanical limiting speed. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 2.18 (2550 against 1170 kN), and the Pu figure 245 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 750 r/min thermal reference speed and 950 r/min mechanical limiting speed. Fit practice for NNCL4952-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1170/2550 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4952-CV?", "a": "SKF NNCL 4952 CV is a double-row full-complement cylindrical roller bearing with 260 mm bore, 360 mm OD and 100 mm width per ISO 15. SKF lists C 1170 kN, C0 2550 kN, Pu 245 kN, reference speed 750 r/min and limiting speed 950 r/min, mass about 31000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4952-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4952-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4952-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×360×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4952-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×360×100 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4952-CV", "SKF NNCL 4952 CV" ], "locale_variants": {} }, { "sku": "NNCL4956-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4956 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 380, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1210, "static_load_kN": 2700, "fatigue_load_limit_kN": 255, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 33000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4956-CV is the 280 mm bore entry in the NNCL4900 range: a 280×380×100 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1210 kN / C0 2700 kN. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Load-per-bore for the 280 mm seat is about 4.32 kN/mm, typical of dimension series 49 (compact heavy section); use C0 2700 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 280 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1210/2700 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4956-CV?", "a": "SKF NNCL 4956 CV is a double-row full-complement cylindrical roller bearing with 280 mm bore, 380 mm OD and 100 mm width per ISO 15. SKF lists C 1210 kN, C0 2700 kN, Pu 255 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 33000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4956-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4956-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4956-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×380×100 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4956-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×380×100 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4956-CV", "SKF NNCL 4956 CV" ], "locale_variants": {} }, { "sku": "NNCL4960-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4960 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 420, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1680, "static_load_kN": 3750, "fatigue_load_limit_kN": 355, "max_rpm": 800, "reference_speed_rpm": 670, "limiting_speed_rpm": 800, "weight_g": 52000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNCL4960-CV is the 300 mm bore entry in the NNCL4900 range: a 300×420×118 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1680 kN / C0 3750 kN. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 60.0 mm and the catalogue mass 52000 g; at 1680 kN dynamic rating this is roughly 5.60 kN of C per millimetre of bore before application factors. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 300 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "The 1680/3750 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4960-CV?", "a": "SKF NNCL 4960 CV is a double-row full-complement cylindrical roller bearing with 300 mm bore, 420 mm OD and 118 mm width per ISO 15. SKF lists C 1680 kN, C0 3750 kN, Pu 355 kN, reference speed 670 r/min and limiting speed 800 r/min, mass about 52000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4960-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4960-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4960-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×420×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4960-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×420×118 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4960-CV", "SKF NNCL 4960 CV" ], "locale_variants": {} }, { "sku": "NNCL4964-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4964 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 440, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1760, "static_load_kN": 4050, "fatigue_load_limit_kN": 375, "max_rpm": 750, "reference_speed_rpm": 600, "limiting_speed_rpm": 750, "weight_g": 55000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNCL 4964 CV resolves to a 320×440×118 mm double-row full-complement cylindrical roller bearing (dimension series 49 (compact heavy section)); a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Reading the order-string suffix CV: the full-complement execution — extra rollers replace the cage, trading speed for maximum radial capacity and stiffness. Selection arithmetic: C0/C ≈ 2.30 (4050 against 1760 kN), and the Pu figure 375 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 600 r/min thermal reference speed and 750 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "The 1760/4050 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4964-CV?", "a": "SKF NNCL 4964 CV is a double-row full-complement cylindrical roller bearing with 320 mm bore, 440 mm OD and 118 mm width per ISO 15. SKF lists C 1760 kN, C0 4050 kN, Pu 375 kN, reference speed 600 r/min and limiting speed 750 r/min, mass about 55000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4964-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4964-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4964-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×440×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4964-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×440×118 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4964-CV", "SKF NNCL 4964 CV" ], "locale_variants": {} }, { "sku": "NNCL4968-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4968 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 460, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1790, "static_load_kN": 4250, "fatigue_load_limit_kN": 390, "max_rpm": 700, "reference_speed_rpm": 560, "limiting_speed_rpm": 700, "weight_g": 58000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4968 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 340×460×118 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 58000 g. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 2.37 (4250 against 1790 kN), and the Pu figure 390 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 560 r/min thermal reference speed and 700 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks", "mining shovel and dragline pivots" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "The 1790/4250 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4968-CV?", "a": "SKF NNCL 4968 CV is a double-row full-complement cylindrical roller bearing with 340 mm bore, 460 mm OD and 118 mm width per ISO 15. SKF lists C 1790 kN, C0 4250 kN, Pu 390 kN, reference speed 560 r/min and limiting speed 700 r/min, mass about 58000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4968-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4968-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4968-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×460×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4968-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 340×460×118 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4968-CV", "SKF NNCL 4968 CV" ], "locale_variants": {} }, { "sku": "NNCL4972-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4972 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 480, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1830, "static_load_kN": 4500, "fatigue_load_limit_kN": 405, "max_rpm": 670, "reference_speed_rpm": 530, "limiting_speed_rpm": 670, "weight_g": 61000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNCL 4972 CV denotes a double-row full-complement cylindrical roller bearing on the ISO 15 360×480×118 mm envelope, dimension series 49 (compact heavy section), with catalogue mass 61000 g. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. With C 1830 kN and C0 4500 kN, size the bearing on the 360×480 mm ISO 15 envelope and check the 405 kN Pu against the equivalent-load floor; the catalogue lists 530 r/min thermal reference speed and 670 r/min mechanical limiting speed. Assembly note: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1830/4500 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4972-CV?", "a": "SKF NNCL 4972 CV is a double-row full-complement cylindrical roller bearing with 360 mm bore, 480 mm OD and 118 mm width per ISO 15. SKF lists C 1830 kN, C0 4500 kN, Pu 405 kN, reference speed 530 r/min and limiting speed 670 r/min, mass about 61000 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4972-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4972-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4972-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×480×118 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4972-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 360×480×118 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4972-CV", "SKF NNCL 4972 CV" ], "locale_variants": {} }, { "sku": "NNCL4976-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4976 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 520, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2380, "static_load_kN": 5700, "fatigue_load_limit_kN": 500, "max_rpm": 630, "reference_speed_rpm": 500, "limiting_speed_rpm": 630, "weight_g": 90500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNCL 4976 CV is a double-row full-complement cylindrical roller bearing sized 380×520×140 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNCL configuration means a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set; functionally the bearing is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 70.0 mm and the catalogue mass 90500 g; at 2380 kN dynamic rating this is roughly 6.26 kN of C per millimetre of bore before application factors. Fit practice for NNCL4976-CV: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2380/5700 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4976-CV?", "a": "SKF NNCL 4976 CV is a double-row full-complement cylindrical roller bearing with 380 mm bore, 520 mm OD and 140 mm width per ISO 15. SKF lists C 2380 kN, C0 5700 kN, Pu 500 kN, reference speed 500 r/min and limiting speed 630 r/min, mass about 90500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4976-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4976-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4976-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×520×140 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4976-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×520×140 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4976-CV", "SKF NNCL 4976 CV" ], "locale_variants": {} }, { "sku": "NNCL4980-CV", "brand": "SKF", "manufacturer_designation": "SKF NNCL 4980 CV", "series": "NNCL4900-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 540, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2420, "static_load_kN": 6000, "fatigue_load_limit_kN": 520, "max_rpm": 600, "reference_speed_rpm": 480, "limiting_speed_rpm": 600, "weight_g": 94500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 400 mm shaft, SKF lists NNCL4980-CV as double-row full-complement cylindrical roller: 540 mm OD, 140 mm wide, Pu 520 kN, the catalogue lists 480 r/min thermal reference speed and 600 r/min mechanical limiting speed. Structurally, the NNCL design has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. In arrangement terms it is non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 400 mm seat is about 6.05 kN/mm, typical of dimension series 49 (compact heavy section); use C0 6000 kN for static checks such as crane hook blocks standing under load. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 400 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining shovel and dragline pivots", "steelmaking and heavy crane sheaves", "large offshore winch and hook blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "roller smearing between the uncaged rollers during slow skidding starts under heavy static load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "uneven row loading from misalignment, concentrating fatigue on one row of the double complement", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.", "Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "The 2420/6000 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNCL4980-CV?", "a": "SKF NNCL 4980 CV is a double-row full-complement cylindrical roller bearing with 400 mm bore, 540 mm OD and 140 mm width per ISO 15. SKF lists C 2420 kN, C0 6000 kN, Pu 520 kN, reference speed 480 r/min and limiting speed 600 r/min, mass about 94500 g." }, { "q": "What does the NNCL designation and CV suffix mean?", "a": "Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set." }, { "q": "Can NNCL4980-CV take axial load and locate the shaft?", "a": "No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement." }, { "q": "How does NNCL4980-CV compare with the other executions in the same envelope?", "a": "NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement." }, { "q": "What limits the service life of this bearing most often?", "a": "On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently." } ], "cross_ref": [ { "equiv_sku": "NNC4980-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×540×140 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NNCF4980-CV", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×540×140 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNCL4980-CV", "SKF NNCL 4980 CV" ], "locale_variants": {} }, { "sku": "NNF5004-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5004 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 42, "B_mm": 30, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 45.7, "static_load_kN": 55, "fatigue_load_limit_kN": 5.7, "max_rpm": 3400, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3400, "weight_g": 200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 20 mm shaft, SKF lists NNF5004-ADB-2LSV as sealed double-row full-complement cylindrical roller: 42 mm OD, 30 mm wide, Pu 5.7 kN, with a sealed limiting speed of 3,400 r/min. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The radial section height is 11.0 mm and the catalogue mass 200 g; at 45.7 kN dynamic rating this is roughly 2.29 kN of C per millimetre of bore before application factors. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "small construction-machinery pulleys", "crane sheave and hook blocks without external lubrication supply" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (29 mm inner-assembly width) differs from the overall B 30 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 30 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 45.7/55 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5004-ADB-2LSV?", "a": "SKF NNF 5004 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 20 mm bore, 42 mm OD and 30 mm width per ISO 15. SKF lists C 45.7 kN, C0 55 kN, Pu 5.7 kN, limiting speed 3,400 r/min (sealed execution), mass about 200 g. Inner-assembly width B1 is 29 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5004-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5004-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5004-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 20×42×30 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5004-ADB-2LSV", "SKF NNF 5004 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5005-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5005 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 47, "B_mm": 30, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 50.1, "static_load_kN": 65.5, "fatigue_load_limit_kN": 6.8, "max_rpm": 3000, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3000, "weight_g": 240, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5005-ADB-2LSV is the 25 mm bore entry in the NNF5000 range: a 25×47×30 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 50.1 kN / C0 65.5 kN. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 25 mm seat is about 2.00 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 65.5 kN for static checks such as crane hook blocks standing under load. Fit practice for NNF5005-ADB-2LSV: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "small construction-machinery pulleys", "crane sheave and hook blocks without external lubrication supply" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (29 mm inner-assembly width) differs from the overall B 30 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 30 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 50.1/65.5 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5005-ADB-2LSV?", "a": "SKF NNF 5005 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 25 mm bore, 47 mm OD and 30 mm width per ISO 15. SKF lists C 50.1 kN, C0 65.5 kN, Pu 6.8 kN, limiting speed 3,000 r/min (sealed execution), mass about 240 g. Inner-assembly width B1 is 29 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5005-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5005-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5005-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 25×47×30 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5005-ADB-2LSV", "SKF NNF 5005 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5006-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5006 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 55, "B_mm": 34, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 57.2, "static_load_kN": 75, "fatigue_load_limit_kN": 7.8, "max_rpm": 2600, "reference_speed_rpm": 2600, "limiting_speed_rpm": 2600, "weight_g": 370, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5006 ADB-2LSV denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 30×55×34 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 370 g. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. With C 57.2 kN and C0 75 kN, size the bearing on the 30×55 mm ISO 15 envelope and check the 7.8 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 2,600 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "mobile-crane rope sheaves", "construction and access-machinery pulleys", "conveyor snub pulleys in dirty environments" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (33 mm inner-assembly width) differs from the overall B 34 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 34 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 57.2/75 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5006-ADB-2LSV?", "a": "SKF NNF 5006 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 30 mm bore, 55 mm OD and 34 mm width per ISO 15. SKF lists C 57.2 kN, C0 75 kN, Pu 7.8 kN, limiting speed 2,600 r/min (sealed execution), mass about 370 g. Inner-assembly width B1 is 33 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5006-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5006-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5006-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 30×55×34 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5006-ADB-2LSV", "SKF NNF 5006 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5007-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5007 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 62, "B_mm": 36, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 70.4, "static_load_kN": 98, "fatigue_load_limit_kN": 10.6, "max_rpm": 2200, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2200, "weight_g": 480, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNF 5007 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing sized 35×62×36 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.5. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.39 (98 against 70.4 kN), and the Pu figure 10.6 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 2,200 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Fit practice for NNF5007-ADB-2LSV: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mobile-crane rope sheaves", "construction and access-machinery pulleys", "conveyor snub pulleys in dirty environments" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (35 mm inner-assembly width) differs from the overall B 36 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 36 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 70.4/98 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5007-ADB-2LSV?", "a": "SKF NNF 5007 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 35 mm bore, 62 mm OD and 36 mm width per ISO 15. SKF lists C 70.4 kN, C0 98 kN, Pu 10.6 kN, limiting speed 2,200 r/min (sealed execution), mass about 480 g. Inner-assembly width B1 is 35 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5007-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5007-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5007-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 35×62×36 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5007-ADB-2LSV", "SKF NNF 5007 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5008-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5008 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 68, "B_mm": 38, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 85.8, "static_load_kN": 116, "fatigue_load_limit_kN": 13.2, "max_rpm": 2000, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2000, "weight_g": 560, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 40 mm shaft, SKF lists NNF5008-ADB-2LSV as sealed double-row full-complement cylindrical roller: 68 mm OD, 38 mm wide, Pu 13.2 kN, with a sealed limiting speed of 2,000 r/min. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 85.8 kN and C0 116 kN, size the bearing on the 40×68 mm ISO 15 envelope and check the 13.2 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 2,000 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "conveyor snub pulleys in dirty environments", "mobile-crane rope sheaves", "construction and access-machinery pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (37 mm inner-assembly width) differs from the overall B 38 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 38 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 68 mm raceway.", "The 85.8/116 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5008-ADB-2LSV?", "a": "SKF NNF 5008 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 40 mm bore, 68 mm OD and 38 mm width per ISO 15. SKF lists C 85.8 kN, C0 116 kN, Pu 13.2 kN, limiting speed 2,000 r/min (sealed execution), mass about 560 g. Inner-assembly width B1 is 37 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5008-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5008-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5008-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 40×68×38 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5008-ADB-2LSV", "SKF NNF 5008 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5009-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5009 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 75, "B_mm": 40, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 102, "static_load_kN": 146, "fatigue_load_limit_kN": 17, "max_rpm": 1800, "reference_speed_rpm": 1800, "limiting_speed_rpm": 1800, "weight_g": 700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5009 ADB-2LSV resolves to a 45×75×40 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Selection arithmetic: C0/C ≈ 1.43 (146 against 102 kN), and the Pu figure 17 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 1,800 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 45 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "conveyor snub pulleys in dirty environments", "mobile-crane rope sheaves", "construction and access-machinery pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (39 mm inner-assembly width) differs from the overall B 40 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 75 mm raceway.", "The 102/146 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5009-ADB-2LSV?", "a": "SKF NNF 5009 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 45 mm bore, 75 mm OD and 40 mm width per ISO 15. SKF lists C 102 kN, C0 146 kN, Pu 17 kN, limiting speed 1,800 r/min (sealed execution), mass about 700 g. Inner-assembly width B1 is 39 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5009-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5009-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5009-CV", "equiv_brand": "SKF", "level": "full", "note": "Open full-complement counterpart on the same 45×75×40 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings match the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5009-ADB-2LSV", "SKF NNF 5009 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5010-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5010 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 80, "B_mm": 40, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 108, "static_load_kN": 160, "fatigue_load_limit_kN": 18.6, "max_rpm": 1700, "reference_speed_rpm": 1700, "limiting_speed_rpm": 1700, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 50 mm shaft, SKF lists NNF5010-ADB-2LSV as sealed double-row full-complement cylindrical roller: 80 mm OD, 40 mm wide, Pu 18.6 kN, with a sealed limiting speed of 1,700 r/min. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix ADB-2LSV: nitrile-rubber contact seals (2LS) on both sides in the ADB snap-ring/ring-groove build, delivered grease-filled. With C 108 kN and C0 160 kN, size the bearing on the 50×80 mm ISO 15 envelope and check the 18.6 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 1,700 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 50 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "conveyor snub pulleys in dirty environments", "mobile-crane rope sheaves", "construction and access-machinery pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (39 mm inner-assembly width) differs from the overall B 40 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 80 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 108/160 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5010-ADB-2LSV?", "a": "SKF NNF 5010 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 50 mm bore, 80 mm OD and 40 mm width per ISO 15. SKF lists C 108 kN, C0 160 kN, Pu 18.6 kN, limiting speed 1,700 r/min (sealed execution), mass about 760 g. Inner-assembly width B1 is 39 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5010-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5010-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5010-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 50×80×40 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5010-ADB-2LSV", "SKF NNF 5010 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5011-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5011 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 90, "B_mm": 46, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 128, "static_load_kN": 193, "fatigue_load_limit_kN": 22.8, "max_rpm": 1500, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1500, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5011-ADB-2LSV is the 55 mm bore entry in the NNF5000 range: a 55×90×46 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 128 kN / C0 193 kN. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Selection arithmetic: C0/C ≈ 1.51 (193 against 128 kN), and the Pu figure 22.8 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 1,500 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "conveyor snub pulleys in dirty environments", "mobile-crane rope sheaves", "construction and access-machinery pulleys" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (45 mm inner-assembly width) differs from the overall B 46 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 128/193 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5011-ADB-2LSV?", "a": "SKF NNF 5011 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 55 mm bore, 90 mm OD and 46 mm width per ISO 15. SKF lists C 128 kN, C0 193 kN, Pu 22.8 kN, limiting speed 1,500 r/min (sealed execution), mass about 1200 g. Inner-assembly width B1 is 45 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5011-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5011-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5011-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 55×90×46 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5011-ADB-2LSV", "SKF NNF 5011 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5012-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5012 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 95, "B_mm": 46, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 134, "static_load_kN": 208, "fatigue_load_limit_kN": 25, "max_rpm": 1400, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1400, "weight_g": 1250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5012 ADB-2LSV resolves to a 60×95×46 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNF5012-ADB-2LSV: SKF publishes only a limiting speed of 1,400 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 1250 g covers the complete catalogue execution including factory grease fill and both seals. Fit practice for NNF5012-ADB-2LSV: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (45 mm inner-assembly width) differs from the overall B 46 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 95 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 134/208 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5012-ADB-2LSV?", "a": "SKF NNF 5012 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 60 mm bore, 95 mm OD and 46 mm width per ISO 15. SKF lists C 134 kN, C0 208 kN, Pu 25 kN, limiting speed 1,400 r/min (sealed execution), mass about 1250 g. Inner-assembly width B1 is 45 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5012-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5012-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5012-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 60×95×46 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5012-ADB-2LSV", "SKF NNF 5012 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5013-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5013 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 100, "B_mm": 46, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 138, "static_load_kN": 224, "fatigue_load_limit_kN": 26.5, "max_rpm": 1300, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1300, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNF 5013 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing sized 65×100×46 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.5. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The radial section height is 17.5 mm and the catalogue mass 1350 g; at 138 kN dynamic rating this is roughly 2.12 kN of C per millimetre of bore before application factors. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (45 mm inner-assembly width) differs from the overall B 46 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 100 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 138/224 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5013-ADB-2LSV?", "a": "SKF NNF 5013 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 65 mm bore, 100 mm OD and 46 mm width per ISO 15. SKF lists C 138 kN, C0 224 kN, Pu 26.5 kN, limiting speed 1,300 r/min (sealed execution), mass about 1350 g. Inner-assembly width B1 is 45 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5013-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5013-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5013-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 65×100×46 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5013-ADB-2LSV", "SKF NNF 5013 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5014-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5014 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 110, "B_mm": 54, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 187, "static_load_kN": 285, "fatigue_load_limit_kN": 34.5, "max_rpm": 1200, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1200, "weight_g": 1850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 70 mm shaft, SKF lists NNF5014-ADB-2LSV as sealed double-row full-complement cylindrical roller: 110 mm OD, 54 mm wide, Pu 34.5 kN, with a sealed limiting speed of 1,200 r/min. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 70 mm seat is about 2.67 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 285 kN for static checks such as crane hook blocks standing under load. Fit practice for NNF5014-ADB-2LSV: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (53 mm inner-assembly width) differs from the overall B 54 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 187/285 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5014-ADB-2LSV?", "a": "SKF NNF 5014 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 70 mm bore, 110 mm OD and 54 mm width per ISO 15. SKF lists C 187 kN, C0 285 kN, Pu 34.5 kN, limiting speed 1,200 r/min (sealed execution), mass about 1850 g. Inner-assembly width B1 is 53 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5014-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5014-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5014-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 70×110×54 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5014-ADB-2LSV", "SKF NNF 5014 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5015-ADB-2LSV", "brand": "SKF", "manufacturer_designation": "SKF NNF 5015 ADB-2LSV", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 115, "B_mm": 54, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 224, "static_load_kN": 310, "fatigue_load_limit_kN": 40, "max_rpm": 1100, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1100, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5015-ADB-2LSV is the 75 mm bore entry in the NNF5000 range: a 75×115×54 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 224 kN / C0 310 kN. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix ADB-2LSV: nitrile-rubber contact seals (2LS) on both sides in the ADB snap-ring/ring-groove build, delivered grease-filled. With C 224 kN and C0 310 kN, size the bearing on the 75×115 mm ISO 15 envelope and check the 40 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 1,100 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 75 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (53 mm inner-assembly width) differs from the overall B 54 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 115 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 224/310 kN ratings are SKF catalogue 17000 (2018) values for the ADB-2LSV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5015-ADB-2LSV?", "a": "SKF NNF 5015 ADB-2LSV is a sealed double-row full-complement cylindrical roller bearing with 75 mm bore, 115 mm OD and 54 mm width per ISO 15. SKF lists C 224 kN, C0 310 kN, Pu 40 kN, limiting speed 1,100 r/min (sealed execution), mass about 1950 g. Inner-assembly width B1 is 53 mm." }, { "q": "What does the NNF designation and ADB-2LSV suffix mean?", "a": "The ADB-2LSV suffix denotes nitrile-rubber contact seals (2LS) on both sides with the ADB snap-ring/ring-groove build; the bearing ships grease-filled. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5015-ADB-2LSV take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5015-ADB-2LSV compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5015-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 75×115×54 mm envelope; this ADB-2LSV row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5015-ADB-2LSV", "SKF NNF 5015 ADB-2LSV" ], "locale_variants": {} }, { "sku": "NNF5016-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5016 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 125, "B_mm": 60, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 251, "static_load_kN": 415, "fatigue_load_limit_kN": 53, "max_rpm": 1000, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1000, "weight_g": 2700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNF 5016 B-2LS is a sealed double-row full-complement cylindrical roller bearing sized 80×125×60 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.5. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 80 mm seat is about 3.14 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 415 kN for static checks such as crane hook blocks standing under load. Fit practice for NNF5016-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (59 mm inner-assembly width) differs from the overall B 60 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 251/415 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5016-B-2LS?", "a": "SKF NNF 5016 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 80 mm bore, 125 mm OD and 60 mm width per ISO 15. SKF lists C 251 kN, C0 415 kN, Pu 53 kN, limiting speed 1,000 r/min (sealed execution), mass about 2700 g. Inner-assembly width B1 is 59 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5016-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5016-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5016-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 80×125×60 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5016-B-2LS", "SKF NNF 5016 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5017-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5017 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 130, "B_mm": 60, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 270, "static_load_kN": 430, "fatigue_load_limit_kN": 55, "max_rpm": 1000, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1000, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 85 mm shaft, SKF lists NNF5017-B-2LS as sealed double-row full-complement cylindrical roller: 130 mm OD, 60 mm wide, Pu 55 kN, with a sealed limiting speed of 1,000 r/min. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 22.5 mm and the catalogue mass 2850 g; at 270 kN dynamic rating this is roughly 3.18 kN of C per millimetre of bore before application factors. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 85 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "steelwork and scrap-yard crane blocks", "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (59 mm inner-assembly width) differs from the overall B 60 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 270/430 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5017-B-2LS?", "a": "SKF NNF 5017 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 85 mm bore, 130 mm OD and 60 mm width per ISO 15. SKF lists C 270 kN, C0 430 kN, Pu 55 kN, limiting speed 1,000 r/min (sealed execution), mass about 2850 g. Inner-assembly width B1 is 59 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5017-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5017-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5017-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 85×130×60 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5017-B-2LS", "SKF NNF 5017 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5018-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5018 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 140, "B_mm": 67, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 319, "static_load_kN": 550, "fatigue_load_limit_kN": 69.5, "max_rpm": 900, "reference_speed_rpm": 900, "limiting_speed_rpm": 900, "weight_g": 3700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5018 B-2LS resolves to a 90×140×67 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Speed planning for NNF5018-B-2LS: SKF publishes only a limiting speed of 900 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 3700 g covers the complete catalogue execution including factory grease fill and both seals. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks", "bulk-material rope-pulley systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (66 mm inner-assembly width) differs from the overall B 67 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 67 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 319/550 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5018-B-2LS?", "a": "SKF NNF 5018 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 90 mm bore, 140 mm OD and 67 mm width per ISO 15. SKF lists C 319 kN, C0 550 kN, Pu 69.5 kN, limiting speed 900 r/min (sealed execution), mass about 3700 g. Inner-assembly width B1 is 66 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5018-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5018-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5018-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 90×140×67 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5018-B-2LS", "SKF NNF 5018 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5019-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5019 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 145, "B_mm": 67, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 330, "static_load_kN": 570, "fatigue_load_limit_kN": 71, "max_rpm": 900, "reference_speed_rpm": 900, "limiting_speed_rpm": 900, "weight_g": 3900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5019 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 95×145×67 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 3900 g. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.73 (570 against 330 kN), and the Pu figure 71 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 900 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "bulk-material rope-pulley systems", "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (66 mm inner-assembly width) differs from the overall B 67 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 67 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 145 mm raceway.", "The 330/570 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5019-B-2LS?", "a": "SKF NNF 5019 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 95 mm bore, 145 mm OD and 67 mm width per ISO 15. SKF lists C 330 kN, C0 570 kN, Pu 71 kN, limiting speed 900 r/min (sealed execution), mass about 3900 g. Inner-assembly width B1 is 66 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5019-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5019-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNF5019", "equiv_brand": "ISO 15", "level": "verify", "note": "ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range before substituting." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5019-B-2LS", "SKF NNF 5019 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5020-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5020 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 150, "B_mm": 67, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 336, "static_load_kN": 570, "fatigue_load_limit_kN": 68, "max_rpm": 850, "reference_speed_rpm": 850, "limiting_speed_rpm": 850, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5020 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 100×150×67 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 3950 g. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 100 mm seat is about 3.36 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 570 kN for static checks such as crane hook blocks standing under load. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks", "bulk-material rope-pulley systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (66 mm inner-assembly width) differs from the overall B 67 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 67 mm-wide ring and concentrates load.", "The 336/570 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5020-B-2LS?", "a": "SKF NNF 5020 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 100 mm bore, 150 mm OD and 67 mm width per ISO 15. SKF lists C 336 kN, C0 570 kN, Pu 68 kN, limiting speed 850 r/min (sealed execution), mass about 3950 g. Inner-assembly width B1 is 66 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5020-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5020-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5020-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 100×150×67 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5020-B-2LS", "SKF NNF 5020 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5022-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5022 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 170, "B_mm": 80, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 413, "static_load_kN": 695, "fatigue_load_limit_kN": 81.5, "max_rpm": 750, "reference_speed_rpm": 750, "limiting_speed_rpm": 750, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5022-B-2LS is the 110 mm bore entry in the NNF5000 range: a 110×170×80 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 413 kN / C0 695 kN. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. With C 413 kN and C0 695 kN, size the bearing on the 110×170 mm ISO 15 envelope and check the 81.5 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 750 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Fit practice for NNF5022-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy harbour and offshore crane sheaves", "steelwork and scrap-yard crane blocks", "bulk-material rope-pulley systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (79 mm inner-assembly width) differs from the overall B 80 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 413/695 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5022-B-2LS?", "a": "SKF NNF 5022 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 110 mm bore, 170 mm OD and 80 mm width per ISO 15. SKF lists C 413 kN, C0 695 kN, Pu 81.5 kN, limiting speed 750 r/min (sealed execution), mass about 6450 g. Inner-assembly width B1 is 79 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5022-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5022-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5022-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 110×170×80 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5022-B-2LS", "SKF NNF 5022 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5024-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5024 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 180, "B_mm": 80, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 429, "static_load_kN": 750, "fatigue_load_limit_kN": 86.5, "max_rpm": 700, "reference_speed_rpm": 700, "limiting_speed_rpm": 700, "weight_g": 6900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5024 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 120×180×80 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 6900 g. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix B-2LS: nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The radial section height is 30.0 mm and the catalogue mass 6900 g; at 429 kN dynamic rating this is roughly 3.58 kN of C per millimetre of bore before application factors. Fit practice for NNF5024-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (79 mm inner-assembly width) differs from the overall B 80 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 429/750 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5024-B-2LS?", "a": "SKF NNF 5024 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 120 mm bore, 180 mm OD and 80 mm width per ISO 15. SKF lists C 429 kN, C0 750 kN, Pu 86.5 kN, limiting speed 700 r/min (sealed execution), mass about 6900 g. Inner-assembly width B1 is 79 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5024-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5024-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5024-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 120×180×80 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5024-B-2LS", "SKF NNF 5024 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5026-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5026 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 200, "B_mm": 95, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 616, "static_load_kN": 1040, "fatigue_load_limit_kN": 120, "max_rpm": 630, "reference_speed_rpm": 630, "limiting_speed_rpm": 630, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5026-B-2LS is the 130 mm bore entry in the NNF5000 range: a 130×200×95 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 616 kN / C0 1040 kN. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Load-per-bore for the 130 mm seat is about 4.74 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 1040 kN for static checks such as crane hook blocks standing under load. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (94 mm inner-assembly width) differs from the overall B 95 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 616/1040 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5026-B-2LS?", "a": "SKF NNF 5026 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 130 mm bore, 200 mm OD and 95 mm width per ISO 15. SKF lists C 616 kN, C0 1040 kN, Pu 120 kN, limiting speed 630 r/min (sealed execution), mass about 10500 g. Inner-assembly width B1 is 94 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5026-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5026-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5026-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 130×200×95 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5026-B-2LS", "SKF NNF 5026 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5028-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5028 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 210, "B_mm": 95, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 644, "static_load_kN": 1120, "fatigue_load_limit_kN": 127, "max_rpm": 600, "reference_speed_rpm": 600, "limiting_speed_rpm": 600, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NNF 5028 B-2LS is a sealed double-row full-complement cylindrical roller bearing sized 140×210×95 mm — a dimension series 50 (compact heavy section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.5. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNF5028-B-2LS: SKF publishes only a limiting speed of 600 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 11000 g covers the complete catalogue execution including factory grease fill and both seals. Fit practice for NNF5028-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (94 mm inner-assembly width) differs from the overall B 95 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 210 mm raceway.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 644/1120 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5028-B-2LS?", "a": "SKF NNF 5028 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 140 mm bore, 210 mm OD and 95 mm width per ISO 15. SKF lists C 644 kN, C0 1120 kN, Pu 127 kN, limiting speed 600 r/min (sealed execution), mass about 11000 g. Inner-assembly width B1 is 94 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5028-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5028-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5028-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 140×210×95 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5028-B-2LS", "SKF NNF 5028 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5030-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5030 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 225, "B_mm": 100, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 748, "static_load_kN": 1290, "fatigue_load_limit_kN": 143, "max_rpm": 560, "reference_speed_rpm": 560, "limiting_speed_rpm": 560, "weight_g": 13500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 150 mm shaft, SKF lists NNF5030-B-2LS as sealed double-row full-complement cylindrical roller: 225 mm OD, 100 mm wide, Pu 143 kN, with a sealed limiting speed of 560 r/min. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNF5030-B-2LS: SKF publishes only a limiting speed of 560 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 13500 g covers the complete catalogue execution including factory grease fill and both seals. Fit practice for NNF5030-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (99 mm inner-assembly width) differs from the overall B 100 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 748/1290 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5030-B-2LS?", "a": "SKF NNF 5030 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 150 mm bore, 225 mm OD and 100 mm width per ISO 15. SKF lists C 748 kN, C0 1290 kN, Pu 143 kN, limiting speed 560 r/min (sealed execution), mass about 13500 g. Inner-assembly width B1 is 99 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5030-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5030-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5030-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 150×225×100 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5030-B-2LS", "SKF NNF 5030 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5032-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5032 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 240, "B_mm": 109, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 781, "static_load_kN": 1400, "fatigue_load_limit_kN": 153, "max_rpm": 500, "reference_speed_rpm": 500, "limiting_speed_rpm": 500, "weight_g": 16500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5032 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 160×240×109 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 16500 g. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. With C 781 kN and C0 1400 kN, size the bearing on the 160×240 mm ISO 15 envelope and check the 153 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 500 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (108 mm inner-assembly width) differs from the overall B 109 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 109 mm-wide ring and concentrates load.", "The 781/1400 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5032-B-2LS?", "a": "SKF NNF 5032 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 160 mm bore, 240 mm OD and 109 mm width per ISO 15. SKF lists C 781 kN, C0 1400 kN, Pu 153 kN, limiting speed 500 r/min (sealed execution), mass about 16500 g. Inner-assembly width B1 is 108 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5032-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5032-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5032-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 160×240×109 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5032-B-2LS", "SKF NNF 5032 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5034-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5034 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 260, "B_mm": 122, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1010, "static_load_kN": 1800, "fatigue_load_limit_kN": 193, "max_rpm": 480, "reference_speed_rpm": 480, "limiting_speed_rpm": 480, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5034-B-2LS is the 170 mm bore entry in the NNF5000 range: a 170×260×122 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1010 kN / C0 1800 kN. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Selection arithmetic: C0/C ≈ 1.78 (1800 against 1010 kN), and the Pu figure 193 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 480 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Fit practice for NNF5034-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (121 mm inner-assembly width) differs from the overall B 122 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 122 mm-wide ring and concentrates load.", "The 1010/1800 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5034-B-2LS?", "a": "SKF NNF 5034 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 170 mm bore, 260 mm OD and 122 mm width per ISO 15. SKF lists C 1010 kN, C0 1800 kN, Pu 193 kN, limiting speed 480 r/min (sealed execution), mass about 22500 g. Inner-assembly width B1 is 121 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5034-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5034-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5034-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 170×260×122 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5034-B-2LS", "SKF NNF 5034 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5036-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5036 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 280, "B_mm": 136, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1170, "static_load_kN": 2120, "fatigue_load_limit_kN": 228, "max_rpm": 450, "reference_speed_rpm": 450, "limiting_speed_rpm": 450, "weight_g": 31000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5036 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 180×280×136 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 31000 g. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix B-2LS: nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Selection arithmetic: C0/C ≈ 1.81 (2120 against 1170 kN), and the Pu figure 228 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 450 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Fit practice for NNF5036-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (135 mm inner-assembly width) differs from the overall B 136 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "The 1170/2120 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5036-B-2LS?", "a": "SKF NNF 5036 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 180 mm bore, 280 mm OD and 136 mm width per ISO 15. SKF lists C 1170 kN, C0 2120 kN, Pu 228 kN, limiting speed 450 r/min (sealed execution), mass about 31000 g. Inner-assembly width B1 is 135 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5036-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5036-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5036-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 180×280×136 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5036-B-2LS", "SKF NNF 5036 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5038-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5038 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 290, "B_mm": 136, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1190, "static_load_kN": 2200, "fatigue_load_limit_kN": 236, "max_rpm": 430, "reference_speed_rpm": 430, "limiting_speed_rpm": 430, "weight_g": 31500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NNF5038-B-2LS is the 190 mm bore entry in the NNF5000 range: a 190×290×136 mm sealed double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 1190 kN / C0 2200 kN. The NNF configuration means a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed; functionally the bearing is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. Speed planning for NNF5038-B-2LS: SKF publishes only a limiting speed of 430 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 31500 g covers the complete catalogue execution including factory grease fill and both seals. Assembly note: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Heat steel rings inductively to max 120 °C, and never wash a full-complement unit in a way that displaces rollers.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (135 mm inner-assembly width) differs from the overall B 136 mm; check housing and spacer geometry against both values.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 290 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 290 mm raceway.", "The 1190/2200 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5038-B-2LS?", "a": "SKF NNF 5038 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 190 mm bore, 290 mm OD and 136 mm width per ISO 15. SKF lists C 1190 kN, C0 2200 kN, Pu 236 kN, limiting speed 430 r/min (sealed execution), mass about 31500 g. Inner-assembly width B1 is 135 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5038-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5038-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5038-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 190×290×136 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5038-B-2LS", "SKF NNF 5038 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5040-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5040 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 310, "B_mm": 150, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1450, "static_load_kN": 2900, "fatigue_load_limit_kN": 300, "max_rpm": 400, "reference_speed_rpm": 400, "limiting_speed_rpm": 400, "weight_g": 42000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5040 B-2LS resolves to a 200×310×150 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix B-2LS: nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Load-per-bore for the 200 mm seat is about 7.25 kN/mm, typical of dimension series 50 (compact heavy section, wide); use C0 2900 kN for static checks such as crane hook blocks standing under load. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (149 mm inner-assembly width) differs from the overall B 150 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 1450/2900 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5040-B-2LS?", "a": "SKF NNF 5040 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 200 mm bore, 310 mm OD and 150 mm width per ISO 15. SKF lists C 1450 kN, C0 2900 kN, Pu 300 kN, limiting speed 400 r/min (sealed execution), mass about 42000 g. Inner-assembly width B1 is 149 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5040-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5040-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5040-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 200×310×150 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5040-B-2LS", "SKF NNF 5040 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5044-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5044 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 340, "B_mm": 160, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1610, "static_load_kN": 3100, "fatigue_load_limit_kN": 315, "max_rpm": 360, "reference_speed_rpm": 360, "limiting_speed_rpm": 360, "weight_g": 54000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5044 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 220×340×160 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 54000 g. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. The full complement of extra rollers fitted in place of a cage is reflected in the published speeds and temperature limits. The radial section height is 60.0 mm and the catalogue mass 54000 g; at 1610 kN dynamic rating this is roughly 7.32 kN of C per millimetre of bore before application factors. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (159 mm inner-assembly width) differs from the overall B 160 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 160 mm-wide ring and concentrates load.", "The 1610/3100 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5044-B-2LS?", "a": "SKF NNF 5044 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 220 mm bore, 340 mm OD and 160 mm width per ISO 15. SKF lists C 1610 kN, C0 3100 kN, Pu 315 kN, limiting speed 360 r/min (sealed execution), mass about 54000 g. Inner-assembly width B1 is 159 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5044-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5044-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5044-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 220×340×160 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5044-B-2LS", "SKF NNF 5044 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5048-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5048 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 360, "B_mm": 160, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 1680, "static_load_kN": 3350, "fatigue_load_limit_kN": 335, "max_rpm": 340, "reference_speed_rpm": 340, "limiting_speed_rpm": 340, "weight_g": 57500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NNF 5048 B-2LS denotes a sealed double-row full-complement cylindrical roller bearing on the ISO 15 240×360×160 mm envelope, dimension series 50 (compact heavy section, wide), with catalogue mass 57500 g. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix B-2LS: nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Speed planning for NNF5048-B-2LS: SKF publishes only a limiting speed of 340 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. The mass entry 57500 g covers the complete catalogue execution including factory grease fill and both seals. Fit practice for NNF5048-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (159 mm inner-assembly width) differs from the overall B 160 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "The 1680/3350 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5048-B-2LS?", "a": "SKF NNF 5048 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 240 mm bore, 360 mm OD and 160 mm width per ISO 15. SKF lists C 1680 kN, C0 3350 kN, Pu 335 kN, limiting speed 340 r/min (sealed execution), mass about 57500 g. Inner-assembly width B1 is 159 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5048-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5048-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5048-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 240×360×160 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5048-B-2LS", "SKF NNF 5048 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5052-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5052 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 400, "B_mm": 190, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2420, "static_load_kN": 4650, "fatigue_load_limit_kN": 455, "max_rpm": 300, "reference_speed_rpm": 300, "limiting_speed_rpm": 300, "weight_g": 86000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5052 B-2LS resolves to a 260×400×190 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. Reading the NNF prefix: a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. This makes the execution a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. Reading the order-string suffix B-2LS: nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. With C 2420 kN and C0 4650 kN, size the bearing on the 260×400 mm ISO 15 envelope and check the 455 kN Pu against the equivalent-load floor; SKF publishes only a limiting speed of 300 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Mounting: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. A 260 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems", "mining dragline and shovel rope sheaves" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (189 mm inner-assembly width) differs from the overall B 190 mm; check housing and spacer geometry against both values.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 190 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "The 2420/4650 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5052-B-2LS?", "a": "SKF NNF 5052 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 260 mm bore, 400 mm OD and 190 mm width per ISO 15. SKF lists C 2420 kN, C0 4650 kN, Pu 455 kN, limiting speed 300 r/min (sealed execution), mass about 86000 g. Inner-assembly width B1 is 189 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5052-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5052-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5052-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 260×400×190 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5052-B-2LS", "SKF NNF 5052 B-2LS" ], "locale_variants": {} }, { "sku": "NNF5056-B-2LS", "brand": "SKF", "manufacturer_designation": "SKF NNF 5056 B-2LS", "series": "NNF5000-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 420, "B_mm": 190, "material": "GCr15", "seal_type": "2RS", "clearance": "CN", "tolerance_class": "P0", "cage_type": "none", "dynamic_load_kN": 2550, "static_load_kN": 5000, "fatigue_load_limit_kN": 490, "max_rpm": 280, "reference_speed_rpm": 280, "limiting_speed_rpm": 280, "weight_g": 91000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NNF 5056 B-2LS resolves to a 280×420×190 mm sealed double-row full-complement cylindrical roller bearing (dimension series 50 (compact heavy section, wide)); a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. Structurally, the NNF design has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed. In arrangement terms it is a sealed locating unit for very heavy radial loads; the sealed-for-life execution is the classic crane-sheave bearing. The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Selection arithmetic: C0/C ≈ 1.96 (5000 against 2550 kN), and the Pu figure 490 kN is the fatigue load-limit floor for the SKF life equation; SKF publishes only a limiting speed of 280 r/min for this sealed execution — the seal contact and packed grease, not a thermal reference speed, set the ceiling. Fit practice for NNF5056-B-2LS: mount as a complete sealed unit — never wash out the factory grease; the seals set the speed ceiling, and relubrication, where specified, goes through the ring grooves. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining dragline and shovel rope sheaves", "large offshore hook blocks and jib sheaves", "heavy dock and shipyard crane systems" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "seal-lip wear and grease loss in dusty crane and construction service after the relubrication interval is exceeded", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "grease degradation inside the sealed unit after long high-temperature periods, invisible until noise rises", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "The sealed NNF unit is packed for life with the correct grease — do not heat it above the seal limit or wash it before mounting; damaged lip seals invalidate the heavy-load duty.", "The B1 width (189 mm inner-assembly width) differs from the overall B 190 mm; check housing and spacer geometry against both values.", "Catalogue reference and limiting speeds are different criteria, though only the limiting speed is published for this sealed unit: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 190 mm-wide ring and concentrates load.", "The 2550/5000 kN ratings are SKF catalogue 17000 (2018) values for the B-2LS execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NNF5056-B-2LS?", "a": "SKF NNF 5056 B-2LS is a sealed double-row full-complement cylindrical roller bearing with 280 mm bore, 420 mm OD and 190 mm width per ISO 15. SKF lists C 2550 kN, C0 5000 kN, Pu 490 kN, limiting speed 280 r/min (sealed execution), mass about 91000 g. Inner-assembly width B1 is 189 mm." }, { "q": "What does the NNF designation and B-2LS suffix mean?", "a": "The B-2LS suffix denotes nitrile-rubber contact seals on both sides of a grease-packed full-complement unit. Structurally this execution has a double-row full complement bearing with contact seals on both sides, three integral inner-ring flanges, an annular lube groove in the outer ring and additional lubrication holes in the inner ring, delivered grease-packed." }, { "q": "Can NNF5056-B-2LS take axial load and locate the shaft?", "a": "The sealed NNF unit can guide light axial loads in both directions via the flanged inner ring, but its primary duty is very heavy radial load in sealed positions." }, { "q": "How does NNF5056-B-2LS compare with the other executions in the same envelope?", "a": "The sealed NNF execution shares its envelope with the open NNCF/NNCL/NNC full-complement bearings but is delivered grease-packed with contact seals and a much lower speed ceiling." }, { "q": "Does the sealed NNF bearing need relubrication?", "a": "NNF bearings are delivered grease-packed and sealed for long service; where the design provides relubrication grooves/holes, replenish through them at the prescribed interval. Never wash the bearing out or exceed the seal-limited speed." } ], "cross_ref": [ { "equiv_sku": "NNCF5056-CV", "equiv_brand": "SKF", "level": "partial", "note": "Open full-complement counterpart on the same 280×420×190 mm envelope; this B-2LS row is sealed both sides and grease-packed with a lower limiting speed, and its catalogue ratings differ from the open execution." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.5 sealed double-row full complement cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NNF5056-B-2LS", "SKF NNF 5056 B-2LS" ], "locale_variants": {} }, { "sku": "NU10-500-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 10/500 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 720, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1720, "static_load_kN": 3100, "fatigue_load_limit_kN": 236, "max_rpm": 1100, "reference_speed_rpm": 900, "limiting_speed_rpm": 1100, "weight_g": 135000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 10/500 MA resolves to a 500×720×100 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1720 kN and C0 3100 kN, size the bearing on the 500×720 mm ISO 15 envelope and check the 236 kN Pu against the equivalent-load floor; the catalogue lists 900 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/500 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 720 mm raceway.", "The 1720/3100 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-500-MA?", "a": "SKF NU 10/500 MA is a single-row caged cylindrical roller bearing with 500 mm bore, 720 mm OD and 100 mm width per ISO 15. SKF lists C 1720 kN, C0 3100 kN, Pu 236 kN, reference speed 900 r/min and limiting speed 1,100 r/min, mass about 135000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-500-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-500-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-500-MA", "SKF NU 10/500 MA" ], "locale_variants": {} }, { "sku": "NU10-530-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 10/530 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 530, "D_mm": 780, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2290, "static_load_kN": 4050, "fatigue_load_limit_kN": 305, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 190000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU10-530-MA is the 530 mm bore entry in the NU1000 range: a 530×780×112 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 2290 kN / C0 4050 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The radial section height is 125.0 mm and the catalogue mass 190000 g; at 2290 kN dynamic rating this is roughly 4.32 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 530 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/530, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/530 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 780 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 780 mm raceway.", "The 2290/4050 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-530-MA?", "a": "SKF NU 10/530 MA is a single-row caged cylindrical roller bearing with 530 mm bore, 780 mm OD and 112 mm width per ISO 15. SKF lists C 2290 kN, C0 4050 kN, Pu 305 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 190000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-530-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-530-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-530-MA", "SKF NU 10/530 MA" ], "locale_variants": {} }, { "sku": "NU10-560-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 10/560 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 560, "D_mm": 820, "B_mm": 115, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2330, "static_load_kN": 4250, "fatigue_load_limit_kN": 310, "max_rpm": 1000, "reference_speed_rpm": 750, "limiting_speed_rpm": 1000, "weight_g": 210000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 10/560 MA is a single-row caged cylindrical roller bearing sized 560×820×115 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 560 mm seat is about 4.16 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 4250 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/560, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/560 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 820 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 820 mm raceway.", "The 2330/4250 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-560-MA?", "a": "SKF NU 10/560 MA is a single-row caged cylindrical roller bearing with 560 mm bore, 820 mm OD and 115 mm width per ISO 15. SKF lists C 2330 kN, C0 4250 kN, Pu 310 kN, reference speed 750 r/min and limiting speed 1,000 r/min, mass about 210000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-560-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-560-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-560-MA", "SKF NU 10/560 MA" ], "locale_variants": {} }, { "sku": "NU10-600-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 10/600 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 600, "D_mm": 870, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2750, "static_load_kN": 5100, "fatigue_load_limit_kN": 365, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 240000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 10/600 MA is a single-row caged cylindrical roller bearing sized 600×870×118 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU10-600-MA: the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. The mass entry 240000 g covers the complete catalogue execution. Fit practice for NU10-600-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/600, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/600 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 870 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2750/5100 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-600-MA?", "a": "SKF NU 10/600 MA is a single-row caged cylindrical roller bearing with 600 mm bore, 870 mm OD and 118 mm width per ISO 15. SKF lists C 2750 kN, C0 5100 kN, Pu 365 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 240000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-600-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-600-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-600-MA", "SKF NU 10/600 MA" ], "locale_variants": {} }, { "sku": "NU10-710-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 10/710 ECMA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 710, "D_mm": 1030, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4680, "static_load_kN": 8500, "fatigue_load_limit_kN": 570, "max_rpm": 750, "reference_speed_rpm": 560, "limiting_speed_rpm": 750, "weight_g": 415000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 10/710 ECMA resolves to a 710×1030×140 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 710 mm seat is about 6.59 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 8500 kN for static checks such as crane hook blocks standing under load. Fit practice for NU10-710-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/710, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/710 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "The 4680/8500 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-710-ECMA?", "a": "SKF NU 10/710 ECMA is a single-row caged cylindrical roller bearing with 710 mm bore, 1030 mm OD and 140 mm width per ISO 15. SKF lists C 4680 kN, C0 8500 kN, Pu 570 kN, reference speed 560 r/min and limiting speed 750 r/min, mass about 415000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-710-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-710-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-710-ECMA", "SKF NU 10/710 ECMA" ], "locale_variants": {} }, { "sku": "NU10-750-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 10/750 ECMA/HB1", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 150, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4730, "static_load_kN": 8800, "fatigue_load_limit_kN": 585, "max_rpm": 670, "reference_speed_rpm": 430, "limiting_speed_rpm": 670, "weight_g": 487000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 10/750 ECMA/HB1 is a single-row caged cylindrical roller bearing sized 750×1090×150 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. The radial section height is 170.0 mm and the catalogue mass 487000 g; at 4730 kN dynamic rating this is roughly 6.31 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 750 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 10/750, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 10/750 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 150 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 4730/8800 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU10-750-ECMA-HB1?", "a": "SKF NU 10/750 ECMA/HB1 is a single-row caged cylindrical roller bearing with 750 mm bore, 1090 mm OD and 150 mm width per ISO 15. SKF lists C 4730 kN, C0 8800 kN, Pu 585 kN, reference speed 430 r/min and limiting speed 670 r/min, mass about 487000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU10-750-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU10-750-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU10-500", "equiv_brand": "NTN", "level": "verify", "note": "Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue." }, { "equiv_sku": "NU10", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU10-750-ECMA-HB1", "SKF NU 10/750 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU1005", "brand": "SKF", "manufacturer_designation": "SKF NU 1005", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 47, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 14.2, "static_load_kN": 13.2, "fatigue_load_limit_kN": 1.4, "max_rpm": 18000, "reference_speed_rpm": 18000, "limiting_speed_rpm": 18000, "weight_g": 82, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 25 mm shaft, SKF lists NU1005 as single-row caged cylindrical roller: 47 mm OD, 12 mm wide, Pu 1.4 kN, the catalogue lists 18,000 r/min thermal reference speed and 18,000 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The pressed sheet-steel window-type cage is reflected in the published speeds and temperature limits. With C 14.2 kN and C0 13.2 kN, size the bearing on the 25×47 mm ISO 15 envelope and check the 1.4 kN Pu against the equivalent-load floor; the catalogue lists 18,000 r/min thermal reference speed and 18,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1005, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1005 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 12 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 47 mm raceway.", "The 14.2/13.2 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1005?", "a": "SKF NU 1005 is a single-row caged cylindrical roller bearing with 25 mm bore, 47 mm OD and 12 mm width per ISO 15. SKF lists C 14.2 kN, C0 13.2 kN, Pu 1.4 kN, reference speed 18,000 r/min and limiting speed 18,000 r/min, mass about 82 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1005 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1005 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1005-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 25×47×12 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1005", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1005", "SKF NU 1005" ], "locale_variants": {} }, { "sku": "NU1006", "brand": "SKF", "manufacturer_designation": "SKF NU 1006", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 55, "B_mm": 13, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 17.9, "static_load_kN": 17.3, "fatigue_load_limit_kN": 1.86, "max_rpm": 15000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 15000, "weight_g": 110, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1006 resolves to a 30×55×13 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The pressed sheet-steel window-type cage is reflected in the published speeds and temperature limits. With C 17.9 kN and C0 17.3 kN, size the bearing on the 30×55 mm ISO 15 envelope and check the 1.86 kN Pu against the equivalent-load floor; the catalogue lists 15,000 r/min thermal reference speed and 15,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 30 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1006, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1006 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 13 mm-wide ring and concentrates load.", "The 17.9/17.3 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1006?", "a": "SKF NU 1006 is a single-row caged cylindrical roller bearing with 30 mm bore, 55 mm OD and 13 mm width per ISO 15. SKF lists C 17.9 kN, C0 17.3 kN, Pu 1.86 kN, reference speed 15,000 r/min and limiting speed 15,000 r/min, mass about 110 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1006 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1006 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1006-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 30×55×13 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1006", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1006", "SKF NU 1006" ], "locale_variants": {} }, { "sku": "NU1007-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1007 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 62, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 35.8, "static_load_kN": 38, "fatigue_load_limit_kN": 4.55, "max_rpm": 13000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 13000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1007 ECP is a single-row caged cylindrical roller bearing sized 35×62×14 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.06 (38 against 35.8 kN), and the Pu figure 4.55 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 13,000 r/min thermal reference speed and 13,000 r/min mechanical limiting speed. Fit practice for NU1007-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1007, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1007 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 62 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 62 mm raceway.", "The 35.8/38 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1007-ECP?", "a": "SKF NU 1007 ECP is a single-row caged cylindrical roller bearing with 35 mm bore, 62 mm OD and 14 mm width per ISO 15. SKF lists C 35.8 kN, C0 38 kN, Pu 4.55 kN, reference speed 13,000 r/min and limiting speed 13,000 r/min, mass about 160 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1007-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1007-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1007", "equiv_brand": "NTN", "level": "partial", "note": "Same 35×62×14 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1007", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1007-ECP", "SKF NU 1007 ECP" ], "locale_variants": {} }, { "sku": "NU1008-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1008 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 68, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 25.1, "static_load_kN": 26, "fatigue_load_limit_kN": 3, "max_rpm": 18000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 18000, "weight_g": 230, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1008-ML is the 40 mm bore entry in the NU1000 range: a 40×68×15 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 25.1 kN / C0 26 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. Speed planning for NU1008-ML: the catalogue lists 12,000 r/min thermal reference speed and 18,000 r/min mechanical limiting speed. The mass entry 230 g covers the complete catalogue execution. Fit practice for NU1008-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1008, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1008 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 68 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 68 mm raceway.", "The 25.1/26 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1008-ML?", "a": "SKF NU 1008 ML is a single-row caged cylindrical roller bearing with 40 mm bore, 68 mm OD and 15 mm width per ISO 15. SKF lists C 25.1 kN, C0 26 kN, Pu 3 kN, reference speed 12,000 r/min and limiting speed 18,000 r/min, mass about 230 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1008-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1008-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1008", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×68×15 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1008", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1008-ML", "SKF NU 1008 ML" ], "locale_variants": {} }, { "sku": "NU1009-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1009 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 75, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 44.6, "static_load_kN": 52, "fatigue_load_limit_kN": 6.3, "max_rpm": 11000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 11000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1009 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 45×75×16 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 250 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 44.6 kN and C0 52 kN, size the bearing on the 45×75 mm ISO 15 envelope and check the 6.3 kN Pu against the equivalent-load floor; the catalogue lists 11,000 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. Fit practice for NU1009-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1009, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1009 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 75 mm raceway.", "The 44.6/52 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1009-ECP?", "a": "SKF NU 1009 ECP is a single-row caged cylindrical roller bearing with 45 mm bore, 75 mm OD and 16 mm width per ISO 15. SKF lists C 44.6 kN, C0 52 kN, Pu 6.3 kN, reference speed 11,000 r/min and limiting speed 11,000 r/min, mass about 250 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1009-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1009-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1009", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×75×16 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1009-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×75×16 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1009-ECP", "SKF NU 1009 ECP" ], "locale_variants": {} }, { "sku": "NU1010-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1010 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 80, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 46.8, "static_load_kN": 56, "fatigue_load_limit_kN": 6.7, "max_rpm": 9500, "reference_speed_rpm": 9500, "limiting_speed_rpm": 9500, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 50 mm shaft, SKF lists NU1010-ECP as single-row caged cylindrical roller: 80 mm OD, 16 mm wide, Pu 6.7 kN, the catalogue lists 9,500 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NU1010-ECP: the catalogue lists 9,500 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. The mass entry 270 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1010, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1010 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 16 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 16 mm-wide ring and concentrates load.", "The 46.8/56 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1010-ECP?", "a": "SKF NU 1010 ECP is a single-row caged cylindrical roller bearing with 50 mm bore, 80 mm OD and 16 mm width per ISO 15. SKF lists C 46.8 kN, C0 56 kN, Pu 6.7 kN, reference speed 9,500 r/min and limiting speed 9,500 r/min, mass about 270 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1010-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1010-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1010", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×80×16 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1010", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1010-ECP", "SKF NU 1010 ECP" ], "locale_variants": {} }, { "sku": "NU1011-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1011 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 90, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 57.2, "static_load_kN": 69.5, "fatigue_load_limit_kN": 8.3, "max_rpm": 8500, "reference_speed_rpm": 8500, "limiting_speed_rpm": 8500, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1011 ECP is a single-row caged cylindrical roller bearing sized 55×90×18 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.22 (69.5 against 57.2 kN), and the Pu figure 8.3 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 8,500 r/min thermal reference speed and 8,500 r/min mechanical limiting speed. Fit practice for NU1011-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1011, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1011 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 18 mm-wide ring and concentrates load.", "The 57.2/69.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1011-ECP?", "a": "SKF NU 1011 ECP is a single-row caged cylindrical roller bearing with 55 mm bore, 90 mm OD and 18 mm width per ISO 15. SKF lists C 57.2 kN, C0 69.5 kN, Pu 8.3 kN, reference speed 8,500 r/min and limiting speed 8,500 r/min, mass about 390 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1011-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1011-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1011", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×90×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1011-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×90×18 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1011-ECP", "SKF NU 1011 ECP" ], "locale_variants": {} }, { "sku": "NU1012-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1012 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 95, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 37.4, "static_load_kN": 44, "fatigue_load_limit_kN": 5.3, "max_rpm": 13000, "reference_speed_rpm": 8000, "limiting_speed_rpm": 13000, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1012-ML is the 60 mm bore entry in the NU1000 range: a 60×95×18 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 37.4 kN / C0 44 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 17.5 mm and the catalogue mass 500 g; at 37.4 kN dynamic rating this is roughly 0.62 kN of C per millimetre of bore before application factors. Fit practice for NU1012-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1012, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1012 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 37.4/44 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1012-ML?", "a": "SKF NU 1012 ML is a single-row caged cylindrical roller bearing with 60 mm bore, 95 mm OD and 18 mm width per ISO 15. SKF lists C 37.4 kN, C0 44 kN, Pu 5.3 kN, reference speed 8,000 r/min and limiting speed 13,000 r/min, mass about 500 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1012-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1012-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1012", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×95×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1012", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1012-ML", "SKF NU 1012 ML" ], "locale_variants": {} }, { "sku": "NU1013-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1013 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 100, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 62.7, "static_load_kN": 81.5, "fatigue_load_limit_kN": 9.8, "max_rpm": 7500, "reference_speed_rpm": 7500, "limiting_speed_rpm": 7500, "weight_g": 450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1013 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 65×100×18 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 450 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 62.7 kN and C0 81.5 kN, size the bearing on the 65×100 mm ISO 15 envelope and check the 9.8 kN Pu against the equivalent-load floor; the catalogue lists 7,500 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Fit practice for NU1013-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1013, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1013 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 18 mm-wide ring and concentrates load.", "The 62.7/81.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1013-ECP?", "a": "SKF NU 1013 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 100 mm OD and 18 mm width per ISO 15. SKF lists C 62.7 kN, C0 81.5 kN, Pu 9.8 kN, reference speed 7,500 r/min and limiting speed 7,500 r/min, mass about 450 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1013-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1013-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1013", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×100×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1013-ML", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 65×100×18 mm, but catalogue C/C0 ratings differ between executions (62.7/81.5 vs 38/46.5 kN) and the NU flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1013-ECP", "SKF NU 1013 ECP" ], "locale_variants": {} }, { "sku": "NU1013-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1013 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 100, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 38, "static_load_kN": 46.5, "fatigue_load_limit_kN": 5.5, "max_rpm": 12000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 12000, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 65 mm shaft, SKF lists NU1013-ML as single-row caged cylindrical roller: 100 mm OD, 18 mm wide, Pu 5.5 kN, the catalogue lists 7,500 r/min thermal reference speed and 12,000 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU1013-ML: the catalogue lists 7,500 r/min thermal reference speed and 12,000 r/min mechanical limiting speed. The mass entry 510 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1013, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1013 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 100 mm raceway.", "The 38/46.5 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1013-ML?", "a": "SKF NU 1013 ML is a single-row caged cylindrical roller bearing with 65 mm bore, 100 mm OD and 18 mm width per ISO 15. SKF lists C 38 kN, C0 46.5 kN, Pu 5.5 kN, reference speed 7,500 r/min and limiting speed 12,000 r/min, mass about 510 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1013-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1013-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1013", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×100×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1013-ECP", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 65×100×18 mm, but catalogue C/C0 ratings differ between executions (38/46.5 vs 62.7/81.5 kN) and the NU flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1013-ML", "SKF NU 1013 ML" ], "locale_variants": {} }, { "sku": "NU1014-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 1014 ECP", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 110, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 76.5, "static_load_kN": 93, "fatigue_load_limit_kN": 12, "max_rpm": 7000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 7000, "weight_g": 610, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1014 ECP resolves to a 70×110×20 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NU1014-ECP: the catalogue lists 7,000 r/min thermal reference speed and 7,000 r/min mechanical limiting speed. The mass entry 610 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1014, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1014 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 20 mm-wide ring and concentrates load.", "The 76.5/93 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1014-ECP?", "a": "SKF NU 1014 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 110 mm OD and 20 mm width per ISO 15. SKF lists C 76.5 kN, C0 93 kN, Pu 12 kN, reference speed 7,000 r/min and limiting speed 7,000 r/min, mass about 610 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1014-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1014-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1014", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×110×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1014-ML", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 70×110×20 mm, but catalogue C/C0 ratings differ between executions (76.5/93 vs 56.1/67 kN) and the NU flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1014-ECP", "SKF NU 1014 ECP" ], "locale_variants": {} }, { "sku": "NU1014-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1014 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 110, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 56.1, "static_load_kN": 67, "fatigue_load_limit_kN": 8, "max_rpm": 11000, "reference_speed_rpm": 7000, "limiting_speed_rpm": 11000, "weight_g": 700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1014 ML is a single-row caged cylindrical roller bearing sized 70×110×20 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 20.0 mm and the catalogue mass 700 g; at 56.1 kN dynamic rating this is roughly 0.80 kN of C per millimetre of bore before application factors. Fit practice for NU1014-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1014, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1014 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "The 56.1/67 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1014-ML?", "a": "SKF NU 1014 ML is a single-row caged cylindrical roller bearing with 70 mm bore, 110 mm OD and 20 mm width per ISO 15. SKF lists C 56.1 kN, C0 67 kN, Pu 8 kN, reference speed 7,000 r/min and limiting speed 11,000 r/min, mass about 700 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1014-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1014-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1014", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×110×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1014-ECP", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 70×110×20 mm, but catalogue C/C0 ratings differ between executions (56.1/67 vs 76.5/93 kN) and the NU flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1014-ML", "SKF NU 1014 ML" ], "locale_variants": {} }, { "sku": "NU1015-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1015 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 115, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 58.3, "static_load_kN": 71, "fatigue_load_limit_kN": 8.5, "max_rpm": 10000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 10000, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1015 ML denotes a single-row caged cylindrical roller bearing on the ISO 15 75×115×20 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 750 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. Speed planning for NU1015-ML: the catalogue lists 6,700 r/min thermal reference speed and 10,000 r/min mechanical limiting speed. The mass entry 750 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1015, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1015 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 20 mm-wide ring and concentrates load.", "The 58.3/71 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1015-ML?", "a": "SKF NU 1015 ML is a single-row caged cylindrical roller bearing with 75 mm bore, 115 mm OD and 20 mm width per ISO 15. SKF lists C 58.3 kN, C0 71 kN, Pu 8.5 kN, reference speed 6,700 r/min and limiting speed 10,000 r/min, mass about 750 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1015-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1015-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1015", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×115×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1015", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1015-ML", "SKF NU 1015 ML" ], "locale_variants": {} }, { "sku": "NU1016", "brand": "SKF", "manufacturer_designation": "SKF NU 1016", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 125, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 64.4, "static_load_kN": 78, "fatigue_load_limit_kN": 9.8, "max_rpm": 6300, "reference_speed_rpm": 6300, "limiting_speed_rpm": 6300, "weight_g": 880, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1016 is a single-row caged cylindrical roller bearing sized 80×125×22 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The pressed sheet-steel window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 80 mm seat is about 0.81 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 78 kN for static checks such as crane hook blocks standing under load. Fit practice for NU1016: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1016, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1016 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 64.4/78 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1016?", "a": "SKF NU 1016 is a single-row caged cylindrical roller bearing with 80 mm bore, 125 mm OD and 22 mm width per ISO 15. SKF lists C 64.4 kN, C0 78 kN, Pu 9.8 kN, reference speed 6,300 r/min and limiting speed 6,300 r/min, mass about 880 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1016 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1016 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1016-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×125×22 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1016-ECML", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 80×125×22 mm, but catalogue C/C0 ratings differ between executions (64.4/78 vs 99/127 kN) and the NJ flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1016", "SKF NU 1016" ], "locale_variants": {} }, { "sku": "NU1017-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1017 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 130, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 68.2, "static_load_kN": 86.5, "fatigue_load_limit_kN": 10.8, "max_rpm": 9000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 9000, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1017-ML is the 85 mm bore entry in the NU1000 range: a 85×130×22 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 68.2 kN / C0 86.5 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NU1017-ML: the catalogue lists 6,000 r/min thermal reference speed and 9,000 r/min mechanical limiting speed. The mass entry 1050 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1017, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1017 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 68.2/86.5 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1017-ML?", "a": "SKF NU 1017 ML is a single-row caged cylindrical roller bearing with 85 mm bore, 130 mm OD and 22 mm width per ISO 15. SKF lists C 68.2 kN, C0 86.5 kN, Pu 10.8 kN, reference speed 6,000 r/min and limiting speed 9,000 r/min, mass about 1050 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1017-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1017-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1017", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×130×22 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1017-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×130×22 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP1017-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×130×22 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1017-ML", "SKF NU 1017 ML" ], "locale_variants": {} }, { "sku": "NU1018-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1018 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 140, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 80.9, "static_load_kN": 104, "fatigue_load_limit_kN": 12.7, "max_rpm": 8500, "reference_speed_rpm": 5600, "limiting_speed_rpm": 8500, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 90 mm shaft, SKF lists NU1018-ML as single-row caged cylindrical roller: 140 mm OD, 24 mm wide, Pu 12.7 kN, the catalogue lists 5,600 r/min thermal reference speed and 8,500 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 1.29 (104 against 80.9 kN), and the Pu figure 12.7 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 5,600 r/min thermal reference speed and 8,500 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1018, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1018 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "The 80.9/104 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1018-ML?", "a": "SKF NU 1018 ML is a single-row caged cylindrical roller bearing with 90 mm bore, 140 mm OD and 24 mm width per ISO 15. SKF lists C 80.9 kN, C0 104 kN, Pu 12.7 kN, reference speed 5,600 r/min and limiting speed 8,500 r/min, mass about 1350 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1018-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1018-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1018", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×140×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1018-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×140×24 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1018-ML", "SKF NU 1018 ML" ], "locale_variants": {} }, { "sku": "NU1019-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1019 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 145, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 84.2, "static_load_kN": 110, "fatigue_load_limit_kN": 13.2, "max_rpm": 8000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 8000, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1019 ML is a single-row caged cylindrical roller bearing sized 95×145×24 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU1019-ML: the catalogue lists 5,300 r/min thermal reference speed and 8,000 r/min mechanical limiting speed. The mass entry 1450 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1019, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1019 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 145 mm raceway.", "The 84.2/110 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1019-ML?", "a": "SKF NU 1019 ML is a single-row caged cylindrical roller bearing with 95 mm bore, 145 mm OD and 24 mm width per ISO 15. SKF lists C 84.2 kN, C0 110 kN, Pu 13.2 kN, reference speed 5,300 r/min and limiting speed 8,000 r/min, mass about 1450 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1019-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1019-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1019", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×145×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1019", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1019-ML", "SKF NU 1019 ML" ], "locale_variants": {} }, { "sku": "NU1020-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1020 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 150, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 85.8, "static_load_kN": 114, "fatigue_load_limit_kN": 13.7, "max_rpm": 7500, "reference_speed_rpm": 5000, "limiting_speed_rpm": 7500, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1020 ML resolves to a 100×150×24 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 85.8 kN and C0 114 kN, size the bearing on the 100×150 mm ISO 15 envelope and check the 13.7 kN Pu against the equivalent-load floor; the catalogue lists 5,000 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1020, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1020 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 24 mm-wide ring and concentrates load.", "The 85.8/114 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1020-ML?", "a": "SKF NU 1020 ML is a single-row caged cylindrical roller bearing with 100 mm bore, 150 mm OD and 24 mm width per ISO 15. SKF lists C 85.8 kN, C0 114 kN, Pu 13.7 kN, reference speed 5,000 r/min and limiting speed 7,500 r/min, mass about 1450 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1020-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1020-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1020", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×150×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1020", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1020-ML", "SKF NU 1020 ML" ], "locale_variants": {} }, { "sku": "NU1021-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1021 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 105, "D_mm": 160, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 101, "static_load_kN": 137, "fatigue_load_limit_kN": 16, "max_rpm": 7500, "reference_speed_rpm": 4800, "limiting_speed_rpm": 7500, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1021-ML is the 105 mm bore entry in the NU1000 range: a 105×160×26 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 101 kN / C0 137 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 1.36 (137 against 101 kN), and the Pu figure 16 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,800 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1021, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1021 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 160 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 26 mm-wide ring and concentrates load.", "The 101/137 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1021-ML?", "a": "SKF NU 1021 ML is a single-row caged cylindrical roller bearing with 105 mm bore, 160 mm OD and 26 mm width per ISO 15. SKF lists C 101 kN, C0 137 kN, Pu 16 kN, reference speed 4,800 r/min and limiting speed 7,500 r/min, mass about 1900 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1021-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1021-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1021", "equiv_brand": "NTN", "level": "partial", "note": "Same 105×160×26 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1021", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1021-ML", "SKF NU 1021 ML" ], "locale_variants": {} }, { "sku": "NU1022-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1022 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 170, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 128, "static_load_kN": 166, "fatigue_load_limit_kN": 19.3, "max_rpm": 7000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 7000, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 110 mm shaft, SKF lists NU1022-ML as single-row caged cylindrical roller: 170 mm OD, 28 mm wide, Pu 19.3 kN, the catalogue lists 4,500 r/min thermal reference speed and 7,000 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. With C 128 kN and C0 166 kN, size the bearing on the 110×170 mm ISO 15 envelope and check the 19.3 kN Pu against the equivalent-load floor; the catalogue lists 4,500 r/min thermal reference speed and 7,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1022, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1022 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 128/166 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1022-ML?", "a": "SKF NU 1022 ML is a single-row caged cylindrical roller bearing with 110 mm bore, 170 mm OD and 28 mm width per ISO 15. SKF lists C 128 kN, C0 166 kN, Pu 19.3 kN, reference speed 4,500 r/min and limiting speed 7,000 r/min, mass about 2300 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1022-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1022-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1022", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×170×28 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1022", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1022-ML", "SKF NU 1022 ML" ], "locale_variants": {} }, { "sku": "NU1024-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1024 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 180, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 134, "static_load_kN": 183, "fatigue_load_limit_kN": 20.8, "max_rpm": 6300, "reference_speed_rpm": 4000, "limiting_speed_rpm": 6300, "weight_g": 2550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1024 ML denotes a single-row caged cylindrical roller bearing on the ISO 15 120×180×28 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 2550 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. With C 134 kN and C0 183 kN, size the bearing on the 120×180 mm ISO 15 envelope and check the 20.8 kN Pu against the equivalent-load floor; the catalogue lists 4,000 r/min thermal reference speed and 6,300 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 120 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1024, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1024 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 134/183 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1024-ML?", "a": "SKF NU 1024 ML is a single-row caged cylindrical roller bearing with 120 mm bore, 180 mm OD and 28 mm width per ISO 15. SKF lists C 134 kN, C0 183 kN, Pu 20.8 kN, reference speed 4,000 r/min and limiting speed 6,300 r/min, mass about 2550 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1024-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1024-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1024", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×180×28 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1024", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1024-ML", "SKF NU 1024 ML" ], "locale_variants": {} }, { "sku": "NU1026-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1026 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 200, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 165, "static_load_kN": 224, "fatigue_load_limit_kN": 25, "max_rpm": 5600, "reference_speed_rpm": 3800, "limiting_speed_rpm": 5600, "weight_g": 3850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1026-ML is the 130 mm bore entry in the NU1000 range: a 130×200×33 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 165 kN / C0 224 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 165 kN and C0 224 kN, size the bearing on the 130×200 mm ISO 15 envelope and check the 25 kN Pu against the equivalent-load floor; the catalogue lists 3,800 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1026, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1026 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 33 mm-wide ring and concentrates load.", "The 165/224 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1026-ML?", "a": "SKF NU 1026 ML is a single-row caged cylindrical roller bearing with 130 mm bore, 200 mm OD and 33 mm width per ISO 15. SKF lists C 165 kN, C0 224 kN, Pu 25 kN, reference speed 3,800 r/min and limiting speed 5,600 r/min, mass about 3850 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1026-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1026-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1026", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×200×33 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1026-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×200×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1026-ML", "SKF NU 1026 ML" ], "locale_variants": {} }, { "sku": "NU1028-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1028 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 210, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 179, "static_load_kN": 255, "fatigue_load_limit_kN": 28, "max_rpm": 5300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 5300, "weight_g": 4050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1028 ML is a single-row caged cylindrical roller bearing sized 140×210×33 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 35.0 mm and the catalogue mass 4050 g; at 179 kN dynamic rating this is roughly 1.28 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1028, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1028 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 210 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 210 mm raceway.", "The 179/255 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1028-ML?", "a": "SKF NU 1028 ML is a single-row caged cylindrical roller bearing with 140 mm bore, 210 mm OD and 33 mm width per ISO 15. SKF lists C 179 kN, C0 255 kN, Pu 28 kN, reference speed 3,600 r/min and limiting speed 5,300 r/min, mass about 4050 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1028-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1028-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1028", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1028", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1028-ML", "SKF NU 1028 ML" ], "locale_variants": {} }, { "sku": "NU1030-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1030 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 225, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 198, "static_load_kN": 290, "fatigue_load_limit_kN": 31.5, "max_rpm": 5000, "reference_speed_rpm": 3200, "limiting_speed_rpm": 5000, "weight_g": 4900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1030 ML resolves to a 150×225×35 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NU1030-ML: the catalogue lists 3,200 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. The mass entry 4900 g covers the complete catalogue execution. Fit practice for NU1030-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1030, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1030 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 35 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 35 mm-wide ring and concentrates load.", "The 198/290 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1030-ML?", "a": "SKF NU 1030 ML is a single-row caged cylindrical roller bearing with 150 mm bore, 225 mm OD and 35 mm width per ISO 15. SKF lists C 198 kN, C0 290 kN, Pu 31.5 kN, reference speed 3,200 r/min and limiting speed 5,000 r/min, mass about 4900 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1030-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1030-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1030", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×225×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1030", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1030-ML", "SKF NU 1030 ML" ], "locale_variants": {} }, { "sku": "NU1032-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1032 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 240, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 229, "static_load_kN": 325, "fatigue_load_limit_kN": 35.5, "max_rpm": 4800, "reference_speed_rpm": 3000, "limiting_speed_rpm": 4800, "weight_g": 6000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 160 mm shaft, SKF lists NU1032-ML as single-row caged cylindrical roller: 240 mm OD, 38 mm wide, Pu 35.5 kN, the catalogue lists 3,000 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU1032-ML: the catalogue lists 3,000 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. The mass entry 6000 g covers the complete catalogue execution. Fit practice for NU1032-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1032, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1032 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 38 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 229/325 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1032-ML?", "a": "SKF NU 1032 ML is a single-row caged cylindrical roller bearing with 160 mm bore, 240 mm OD and 38 mm width per ISO 15. SKF lists C 229 kN, C0 325 kN, Pu 35.5 kN, reference speed 3,000 r/min and limiting speed 4,800 r/min, mass about 6000 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1032-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1032-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1032", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×240×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1032", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1032-ML", "SKF NU 1032 ML" ], "locale_variants": {} }, { "sku": "NU1034-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1034 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 260, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 275, "static_load_kN": 400, "fatigue_load_limit_kN": 41.5, "max_rpm": 4300, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4300, "weight_g": 8000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1034 ML denotes a single-row caged cylindrical roller bearing on the ISO 15 170×260×42 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 8000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. Speed planning for NU1034-ML: the catalogue lists 2,800 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. The mass entry 8000 g covers the complete catalogue execution. Fit practice for NU1034-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1034, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1034 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 42 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "The 275/400 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1034-ML?", "a": "SKF NU 1034 ML is a single-row caged cylindrical roller bearing with 170 mm bore, 260 mm OD and 42 mm width per ISO 15. SKF lists C 275 kN, C0 400 kN, Pu 41.5 kN, reference speed 2,800 r/min and limiting speed 4,300 r/min, mass about 8000 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1034-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1034-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1034", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×260×42 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1034-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×260×42 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1034-ML", "SKF NU 1034 ML" ], "locale_variants": {} }, { "sku": "NU1036-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1036 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 280, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 336, "static_load_kN": 475, "fatigue_load_limit_kN": 51, "max_rpm": 4000, "reference_speed_rpm": 2600, "limiting_speed_rpm": 4000, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1036-ML is the 180 mm bore entry in the NU1000 range: a 180×280×46 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 336 kN / C0 475 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ML: the basic (non-E) ML execution with a machined brass cage, standard for the larger and earlier-design sizes. With C 336 kN and C0 475 kN, size the bearing on the 180×280 mm ISO 15 envelope and check the 51 kN Pu against the equivalent-load floor; the catalogue lists 2,600 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 180 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1036, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1036 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 336/475 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1036-ML?", "a": "SKF NU 1036 ML is a single-row caged cylindrical roller bearing with 180 mm bore, 280 mm OD and 46 mm width per ISO 15. SKF lists C 336 kN, C0 475 kN, Pu 51 kN, reference speed 2,600 r/min and limiting speed 4,000 r/min, mass about 10500 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1036-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1036-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1036", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×280×46 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1036-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×280×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1036-ML", "SKF NU 1036 ML" ], "locale_variants": {} }, { "sku": "NU1038-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1038 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 290, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 347, "static_load_kN": 500, "fatigue_load_limit_kN": 53, "max_rpm": 3800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 3800, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1038 ML is a single-row caged cylindrical roller bearing sized 190×290×46 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. With C 347 kN and C0 500 kN, size the bearing on the 190×290 mm ISO 15 envelope and check the 53 kN Pu against the equivalent-load floor; the catalogue lists 2,600 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1038, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1038 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 290 mm raceway.", "The 347/500 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1038-ML?", "a": "SKF NU 1038 ML is a single-row caged cylindrical roller bearing with 190 mm bore, 290 mm OD and 46 mm width per ISO 15. SKF lists C 347 kN, C0 500 kN, Pu 53 kN, reference speed 2,600 r/min and limiting speed 3,800 r/min, mass about 11000 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1038-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1038-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1038", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×290×46 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1038-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×290×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1038-ML", "SKF NU 1038 ML" ], "locale_variants": {} }, { "sku": "NU1040-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1040 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 310, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 380, "static_load_kN": 570, "fatigue_load_limit_kN": 58.5, "max_rpm": 3600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3600, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1040-ML is the 200 mm bore entry in the NU1000 range: a 200×310×51 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 380 kN / C0 570 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 200 mm seat is about 1.90 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 570 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1040, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1040 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 51 mm-wide ring and concentrates load.", "The 380/570 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1040-ML?", "a": "SKF NU 1040 ML is a single-row caged cylindrical roller bearing with 200 mm bore, 310 mm OD and 51 mm width per ISO 15. SKF lists C 380 kN, C0 570 kN, Pu 58.5 kN, reference speed 2,400 r/min and limiting speed 3,600 r/min, mass about 14000 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1040-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1040-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1040", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×310×51 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1040", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1040-ML", "SKF NU 1040 ML" ], "locale_variants": {} }, { "sku": "NU1044-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1044 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 340, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 495, "static_load_kN": 735, "fatigue_load_limit_kN": 73.5, "max_rpm": 3200, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3200, "weight_g": 18500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1044 ML resolves to a 220×340×56 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Load-per-bore for the 220 mm seat is about 2.25 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 735 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1044, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1044 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 340 mm raceway.", "The 495/735 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1044-ML?", "a": "SKF NU 1044 ML is a single-row caged cylindrical roller bearing with 220 mm bore, 340 mm OD and 56 mm width per ISO 15. SKF lists C 495 kN, C0 735 kN, Pu 73.5 kN, reference speed 2,200 r/min and limiting speed 3,200 r/min, mass about 18500 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1044-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1044-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1044", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×340×56 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1044-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×340×56 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1044-ML", "SKF NU 1044 ML" ], "locale_variants": {} }, { "sku": "NU1048-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1048 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 360, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 523, "static_load_kN": 800, "fatigue_load_limit_kN": 78, "max_rpm": 3000, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3000, "weight_g": 19500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1048 ML denotes a single-row caged cylindrical roller bearing on the ISO 15 240×360×56 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 19500 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU1048-ML: the catalogue lists 2,000 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 19500 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1048, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1048 ML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "The 523/800 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1048-ML?", "a": "SKF NU 1048 ML is a single-row caged cylindrical roller bearing with 240 mm bore, 360 mm OD and 56 mm width per ISO 15. SKF lists C 523 kN, C0 800 kN, Pu 78 kN, reference speed 2,000 r/min and limiting speed 3,000 r/min, mass about 19500 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1048-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1048-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1048", "equiv_brand": "NTN", "level": "partial", "note": "Same 240×360×56 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU1048", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1048-ML", "SKF NU 1048 ML" ], "locale_variants": {} }, { "sku": "NU1052-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1052 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 400, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 627, "static_load_kN": 965, "fatigue_load_limit_kN": 96.5, "max_rpm": 2800, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2800, "weight_g": 29500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1052 ML denotes a single-row caged cylindrical roller bearing on the ISO 15 260×400×65 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 29500 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The radial section height is 70.0 mm and the catalogue mass 29500 g; at 627 kN dynamic rating this is roughly 2.41 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1052, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1052 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 65 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 627/965 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1052-ML?", "a": "SKF NU 1052 ML is a single-row caged cylindrical roller bearing with 260 mm bore, 400 mm OD and 65 mm width per ISO 15. SKF lists C 627 kN, C0 965 kN, Pu 96.5 kN, reference speed 1,800 r/min and limiting speed 2,800 r/min, mass about 29500 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1052-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1052-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1052", "equiv_brand": "NTN", "level": "partial", "note": "Same 260×400×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1052-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×400×65 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1052-ML", "SKF NU 1052 ML" ], "locale_variants": {} }, { "sku": "NU1056-ML", "brand": "SKF", "manufacturer_designation": "SKF NU 1056 ML", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 420, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 660, "static_load_kN": 1060, "fatigue_load_limit_kN": 102, "max_rpm": 2600, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2600, "weight_g": 31000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1056 ML is a single-row caged cylindrical roller bearing sized 280×420×65 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 280 mm seat is about 2.36 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 1060 kN for static checks such as crane hook blocks standing under load. Fit practice for NU1056-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1056, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1056 ML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 660/1060 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1056-ML?", "a": "SKF NU 1056 ML is a single-row caged cylindrical roller bearing with 280 mm bore, 420 mm OD and 65 mm width per ISO 15. SKF lists C 660 kN, C0 1060 kN, Pu 102 kN, reference speed 1,700 r/min and limiting speed 2,600 r/min, mass about 31000 g." }, { "q": "What does the NU designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1056-ML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1056-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1056", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1056", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1056-ML", "SKF NU 1056 ML" ], "locale_variants": {} }, { "sku": "NU1060-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1060 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 460, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 858, "static_load_kN": 1370, "fatigue_load_limit_kN": 129, "max_rpm": 2000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "weight_g": 46000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1060 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 300×460×74 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 46000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 858 kN and C0 1370 kN, size the bearing on the 300×460 mm ISO 15 envelope and check the 129 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Fit practice for NU1060-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1060, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1060 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 858/1370 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1060-MA?", "a": "SKF NU 1060 MA is a single-row caged cylindrical roller bearing with 300 mm bore, 460 mm OD and 74 mm width per ISO 15. SKF lists C 858 kN, C0 1370 kN, Pu 129 kN, reference speed 1,500 r/min and limiting speed 2,000 r/min, mass about 46000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1060-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1060-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1060", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ1060-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 300×460×74 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1060-MA", "SKF NU 1060 MA" ], "locale_variants": {} }, { "sku": "NU1064-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1064 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 480, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 880, "static_load_kN": 1430, "fatigue_load_limit_kN": 132, "max_rpm": 1400, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1400, "weight_g": 48500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1064 MA is a single-row caged cylindrical roller bearing sized 320×480×74 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. With C 880 kN and C0 1430 kN, size the bearing on the 320×480 mm ISO 15 envelope and check the 132 kN Pu against the equivalent-load floor; the catalogue lists 1,400 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. Fit practice for NU1064-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1064, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1064 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 74 mm-wide ring and concentrates load.", "The 880/1430 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1064-MA?", "a": "SKF NU 1064 MA is a single-row caged cylindrical roller bearing with 320 mm bore, 480 mm OD and 74 mm width per ISO 15. SKF lists C 880 kN, C0 1430 kN, Pu 132 kN, reference speed 1,400 r/min and limiting speed 1,400 r/min, mass about 48500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1064-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1064-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1064", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ1064-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 320×480×74 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1064-MA", "SKF NU 1064 MA" ], "locale_variants": {} }, { "sku": "NU1072-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1072 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 540, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1100, "static_load_kN": 1830, "fatigue_load_limit_kN": 163, "max_rpm": 1600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1600, "weight_g": 67500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 360 mm shaft, SKF lists NU1072-MA as single-row caged cylindrical roller: 540 mm OD, 82 mm wide, Pu 163 kN, the catalogue lists 1,300 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NU1072-MA: the catalogue lists 1,300 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. The mass entry 67500 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 360 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1072, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1072 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 82 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 540 mm raceway.", "The 1100/1830 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1072-MA?", "a": "SKF NU 1072 MA is a single-row caged cylindrical roller bearing with 360 mm bore, 540 mm OD and 82 mm width per ISO 15. SKF lists C 1100 kN, C0 1830 kN, Pu 163 kN, reference speed 1,300 r/min and limiting speed 1,600 r/min, mass about 67500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1072-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1072-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1072", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1072", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1072-MA", "SKF NU 1072 MA" ], "locale_variants": {} }, { "sku": "NU1076-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1076 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 560, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1140, "static_load_kN": 1930, "fatigue_load_limit_kN": 170, "max_rpm": 1600, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1600, "weight_g": 70000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1076-MA is the 380 mm bore entry in the NU1000 range: a 380×560×82 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1140 kN / C0 1930 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1140 kN and C0 1930 kN, size the bearing on the 380×560 mm ISO 15 envelope and check the 170 kN Pu against the equivalent-load floor; the catalogue lists 1,200 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1076, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1076 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 82 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 560 mm raceway.", "The 1140/1930 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1076-MA?", "a": "SKF NU 1076 MA is a single-row caged cylindrical roller bearing with 380 mm bore, 560 mm OD and 82 mm width per ISO 15. SKF lists C 1140 kN, C0 1930 kN, Pu 170 kN, reference speed 1,200 r/min and limiting speed 1,600 r/min, mass about 70000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1076-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1076-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1076", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ1076-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×560×82 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1076-MA", "SKF NU 1076 MA" ], "locale_variants": {} }, { "sku": "NU1080-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1080 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 600, "B_mm": 90, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1380, "static_load_kN": 2320, "fatigue_load_limit_kN": 196, "max_rpm": 1500, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "weight_g": 90000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1080 MA resolves to a 400×600×90 mm single-row caged cylindrical roller bearing (dimension series 10 (extra-slim OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 400 mm seat is about 3.45 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 2320 kN for static checks such as crane hook blocks standing under load. Fit practice for NU1080-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1080, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1080 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1380/2320 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1080-MA?", "a": "SKF NU 1080 MA is a single-row caged cylindrical roller bearing with 400 mm bore, 600 mm OD and 90 mm width per ISO 15. SKF lists C 1380 kN, C0 2320 kN, Pu 196 kN, reference speed 1,100 r/min and limiting speed 1,500 r/min, mass about 90000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1080-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1080-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1080", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ1080-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×600×90 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1080-MA", "SKF NU 1080 MA" ], "locale_variants": {} }, { "sku": "NU1084-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1084 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 420, "D_mm": 620, "B_mm": 90, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1420, "static_load_kN": 2450, "fatigue_load_limit_kN": 200, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 94000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1084 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 420×620×90 mm envelope, dimension series 10 (extra-slim OD, normal width), with catalogue mass 94000 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Load-per-bore for the 420 mm seat is about 3.38 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 2450 kN for static checks such as crane hook blocks standing under load. Fit practice for NU1084-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1084, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1084 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 90 mm-wide ring and concentrates load.", "The 1420/2450 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1084-MA?", "a": "SKF NU 1084 MA is a single-row caged cylindrical roller bearing with 420 mm bore, 620 mm OD and 90 mm width per ISO 15. SKF lists C 1420 kN, C0 2450 kN, Pu 200 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 94000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1084-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1084-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1084", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1084", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1084-MA", "SKF NU 1084 MA" ], "locale_variants": {} }, { "sku": "NU1092-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1092 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 460, "D_mm": 680, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1650, "static_load_kN": 2850, "fatigue_load_limit_kN": 224, "max_rpm": 1200, "reference_speed_rpm": 950, "limiting_speed_rpm": 1200, "weight_g": 115000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1092 MA is a single-row caged cylindrical roller bearing sized 460×680×100 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 1.73 (2850 against 1650 kN), and the Pu figure 224 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 460 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1092, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1092 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 680 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 680 mm raceway.", "The 1650/2850 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1092-MA?", "a": "SKF NU 1092 MA is a single-row caged cylindrical roller bearing with 460 mm bore, 680 mm OD and 100 mm width per ISO 15. SKF lists C 1650 kN, C0 2850 kN, Pu 224 kN, reference speed 950 r/min and limiting speed 1,200 r/min, mass about 115000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1092-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1092-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1092", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1092", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1092-MA", "SKF NU 1092 MA" ], "locale_variants": {} }, { "sku": "NU1096-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1096 MA", "series": "NU1000-series", "type": "cylindrical_roller", "d_mm": 480, "D_mm": 700, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1680, "static_load_kN": 3000, "fatigue_load_limit_kN": 232, "max_rpm": 1200, "reference_speed_rpm": 900, "limiting_speed_rpm": 1200, "weight_g": 130000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 480 mm shaft, SKF lists NU1096-MA as single-row caged cylindrical roller: 700 mm OD, 100 mm wide, Pu 232 kN, the catalogue lists 900 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 480 mm seat is about 3.50 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 3000 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1096, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1096 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 700 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 700 mm raceway.", "The 1680/3000 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1096-MA?", "a": "SKF NU 1096 MA is a single-row caged cylindrical roller bearing with 480 mm bore, 700 mm OD and 100 mm width per ISO 15. SKF lists C 1680 kN, C0 3000 kN, Pu 232 kN, reference speed 900 r/min and limiting speed 1,200 r/min, mass about 130000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1096-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1096-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1096", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU1096", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1096-MA", "SKF NU 1096 MA" ], "locale_variants": {} }, { "sku": "NU12-500-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 12/500 MA", "series": "NU1200-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 920, "B_mm": 185, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5280, "static_load_kN": 8500, "fatigue_load_limit_kN": 620, "max_rpm": 950, "reference_speed_rpm": 670, "limiting_speed_rpm": 950, "weight_g": 575000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 12/500 MA resolves to a 500×920×185 mm single-row caged cylindrical roller bearing (dimension series 12 (extra-slim OD, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. With C 5280 kN and C0 8500 kN, size the bearing on the 500×920 mm ISO 15 envelope and check the 620 kN Pu against the equivalent-load floor; the catalogue lists 670 r/min thermal reference speed and 950 r/min mechanical limiting speed. Fit practice for NU12-500-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 12 (extra-slim OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 12/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 12/500 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 185 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 185 mm-wide ring and concentrates load.", "The 5280/8500 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU12-500-MA?", "a": "SKF NU 12/500 MA is a single-row caged cylindrical roller bearing with 500 mm bore, 920 mm OD and 185 mm width per ISO 15. SKF lists C 5280 kN, C0 8500 kN, Pu 620 kN, reference speed 670 r/min and limiting speed 950 r/min, mass about 575000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU12-500-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU12-500-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU12", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU12-500-MA", "SKF NU 12/500 MA" ], "locale_variants": {} }, { "sku": "NU12-560-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 12/560 MA", "series": "NU1200-series", "type": "cylindrical_roller", "d_mm": 560, "D_mm": 1030, "B_mm": 206, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 7210, "static_load_kN": 11200, "fatigue_load_limit_kN": 780, "max_rpm": 800, "reference_speed_rpm": 560, "limiting_speed_rpm": 800, "weight_g": 805000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 12/560 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 560×1030×206 mm envelope, dimension series 12 (extra-slim OD, wide), with catalogue mass 805000 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Load-per-bore for the 560 mm seat is about 12.88 kN/mm, typical of dimension series 12 (extra-slim OD, wide); use C0 11200 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 12 (extra-slim OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 12/560, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 12/560 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 206 mm-wide ring and concentrates load.", "The 7210/11200 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU12-560-MA?", "a": "SKF NU 12/560 MA is a single-row caged cylindrical roller bearing with 560 mm bore, 1030 mm OD and 206 mm width per ISO 15. SKF lists C 7210 kN, C0 11200 kN, Pu 780 kN, reference speed 560 r/min and limiting speed 800 r/min, mass about 805000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU12-560-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU12-560-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU12", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU12-560-MA", "SKF NU 12/560 MA" ], "locale_variants": {} }, { "sku": "NU1292-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1292 MA", "series": "NU1200-series", "type": "cylindrical_roller", "d_mm": 460, "D_mm": 830, "B_mm": 165, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4180, "static_load_kN": 6800, "fatigue_load_limit_kN": 510, "max_rpm": 1100, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "weight_g": 415000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1292 MA resolves to a 460×830×165 mm single-row caged cylindrical roller bearing (dimension series 12 (extra-slim OD, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 185.0 mm and the catalogue mass 415000 g; at 4180 kN dynamic rating this is roughly 9.09 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 12 (extra-slim OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 1292, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1292 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 165 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 165 mm-wide ring and concentrates load.", "The 4180/6800 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1292-MA?", "a": "SKF NU 1292 MA is a single-row caged cylindrical roller bearing with 460 mm bore, 830 mm OD and 165 mm width per ISO 15. SKF lists C 4180 kN, C0 6800 kN, Pu 510 kN, reference speed 750 r/min and limiting speed 1,100 r/min, mass about 415000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1292-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1292-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1292", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1292-MA", "SKF NU 1292 MA" ], "locale_variants": {} }, { "sku": "NU18-600-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 18/600 ECMA/HB1", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 600, "D_mm": 730, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 897, "static_load_kN": 2080, "fatigue_load_limit_kN": 108, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 54000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU18-600-ECMA-HB1 is the 600 mm bore entry in the NU1800 range: a 600×730×60 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 897 kN / C0 2080 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. With C 897 kN and C0 2080 kN, size the bearing on the 600×730 mm ISO 15 envelope and check the 108 kN Pu against the equivalent-load floor; the catalogue lists 800 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. Fit practice for NU18-600-ECMA-HB1: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 18/600, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 18/600 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 730 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 730 mm raceway.", "The 897/2080 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU18-600-ECMA-HB1?", "a": "SKF NU 18/600 ECMA/HB1 is a single-row caged cylindrical roller bearing with 600 mm bore, 730 mm OD and 60 mm width per ISO 15. SKF lists C 897 kN, C0 2080 kN, Pu 108 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 54000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU18-600-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU18-600-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU18", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU18-600-ECMA-HB1", "SKF NU 18/600 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU18-800-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 18/800 ECMA", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 800, "D_mm": 980, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1720, "static_load_kN": 4150, "fatigue_load_limit_kN": 190, "max_rpm": 700, "reference_speed_rpm": 530, "limiting_speed_rpm": 700, "weight_g": 137000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 18/800 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 800×980×82 mm envelope, dimension series 18 (ultra-slim section for large shafts), with catalogue mass 137000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 90.0 mm and the catalogue mass 137000 g; at 1720 kN dynamic rating this is roughly 2.15 kN of C per millimetre of bore before application factors. Fit practice for NU18-800-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 18/800, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 18/800 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 82 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 82 mm-wide ring and concentrates load.", "The 1720/4150 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU18-800-ECMA?", "a": "SKF NU 18/800 ECMA is a single-row caged cylindrical roller bearing with 800 mm bore, 980 mm OD and 82 mm width per ISO 15. SKF lists C 1720 kN, C0 4150 kN, Pu 190 kN, reference speed 530 r/min and limiting speed 700 r/min, mass about 137000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU18-800-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU18-800-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU18", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU18-800-ECMA", "SKF NU 18/800 ECMA" ], "locale_variants": {} }, { "sku": "NU18-900-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 18/900 ECMA", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 900, "D_mm": 1090, "B_mm": 85, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1980, "static_load_kN": 4900, "fatigue_load_limit_kN": 240, "max_rpm": 600, "reference_speed_rpm": 450, "limiting_speed_rpm": 600, "weight_g": 169000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 900 mm shaft, SKF lists NU18-900-ECMA as single-row caged cylindrical roller: 1090 mm OD, 85 mm wide, Pu 240 kN, the catalogue lists 450 r/min thermal reference speed and 600 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Selection arithmetic: C0/C ≈ 2.47 (4900 against 1980 kN), and the Pu figure 240 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 450 r/min thermal reference speed and 600 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 18/900, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 18/900 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1090 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1980/4900 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU18-900-ECMA?", "a": "SKF NU 18/900 ECMA is a single-row caged cylindrical roller bearing with 900 mm bore, 1090 mm OD and 85 mm width per ISO 15. SKF lists C 1980 kN, C0 4900 kN, Pu 240 kN, reference speed 450 r/min and limiting speed 600 r/min, mass about 169000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU18-900-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU18-900-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU18", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU18-900-ECMA", "SKF NU 18/900 ECMA" ], "locale_variants": {} }, { "sku": "NU1876-ECMP", "brand": "SKF", "manufacturer_designation": "SKF NU 1876 ECMP", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 480, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 561, "static_load_kN": 1120, "fatigue_load_limit_kN": 98, "max_rpm": 2000, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2000, "weight_g": 20000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1876 ECMP resolves to a 380×480×46 mm single-row caged cylindrical roller bearing (dimension series 18 (ultra-slim section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMP: the E-design ECMP execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. The radial section height is 50.0 mm and the catalogue mass 20000 g; at 561 kN dynamic rating this is roughly 1.48 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1876, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1876 ECMP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "The 561/1120 kN ratings are SKF catalogue 17000 (2018) values for the ECMP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1876-ECMP?", "a": "SKF NU 1876 ECMP is a single-row caged cylindrical roller bearing with 380 mm bore, 480 mm OD and 46 mm width per ISO 15. SKF lists C 561 kN, C0 1120 kN, Pu 98 kN, reference speed 1,300 r/min and limiting speed 2,000 r/min, mass about 20000 g." }, { "q": "What does the NU designation and ECMP suffix mean?", "a": "The ECMP suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1876-ECMP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1876-ECMP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ1876-ECMP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 380×480×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1876-ECMP", "SKF NU 1876 ECMP" ], "locale_variants": {} }, { "sku": "NU1880-MP", "brand": "SKF", "manufacturer_designation": "SKF NU 1880 MP", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 500, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 572, "static_load_kN": 1180, "fatigue_load_limit_kN": 100, "max_rpm": 1900, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1900, "weight_g": 21500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1880 MP resolves to a 400×500×46 mm single-row caged cylindrical roller bearing (dimension series 18 (ultra-slim section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MP suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 50.0 mm and the catalogue mass 21500 g; at 572 kN dynamic rating this is roughly 1.43 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1880, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1880 MP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "The 572/1180 kN ratings are SKF catalogue 17000 (2018) values for the MP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1880-MP?", "a": "SKF NU 1880 MP is a single-row caged cylindrical roller bearing with 400 mm bore, 500 mm OD and 46 mm width per ISO 15. SKF lists C 572 kN, C0 1180 kN, Pu 100 kN, reference speed 1,300 r/min and limiting speed 1,900 r/min, mass about 21500 g." }, { "q": "What does the NU designation and MP suffix mean?", "a": "The MP suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1880-MP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1880-MP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ1880-MP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP1880-MP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×46 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1880-MP", "SKF NU 1880 MP" ], "locale_variants": {} }, { "sku": "NU1884-MP", "brand": "SKF", "manufacturer_designation": "SKF NU 1884 MP", "series": "NU1800-series", "type": "cylindrical_roller", "d_mm": 420, "D_mm": 520, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 572, "static_load_kN": 1200, "fatigue_load_limit_kN": 102, "max_rpm": 1800, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1800, "weight_g": 22000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 1884 MP denotes a single-row caged cylindrical roller bearing on the ISO 15 420×520×46 mm envelope, dimension series 18 (ultra-slim section for large shafts), with catalogue mass 22000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MP: the basic (non-E) MP execution with a machined brass cage, standard for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 2.10 (1200 against 572 kN), and the Pu figure 102 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,200 r/min thermal reference speed and 1,800 r/min mechanical limiting speed. Fit practice for NU1884-MP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1884, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1884 MP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "The 572/1200 kN ratings are SKF catalogue 17000 (2018) values for the MP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1884-MP?", "a": "SKF NU 1884 MP is a single-row caged cylindrical roller bearing with 420 mm bore, 520 mm OD and 46 mm width per ISO 15. SKF lists C 572 kN, C0 1200 kN, Pu 102 kN, reference speed 1,200 r/min and limiting speed 1,800 r/min, mass about 22000 g." }, { "q": "What does the NU designation and MP suffix mean?", "a": "The MP suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1884-MP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1884-MP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1884", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1884-MP", "SKF NU 1884 MP" ], "locale_variants": {} }, { "sku": "NU19-630-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 19/630 ECMA/HB1", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 630, "D_mm": 850, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2240, "static_load_kN": 4400, "fatigue_load_limit_kN": 315, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 168000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 630 mm shaft, SKF lists NU19-630-ECMA-HB1 as single-row caged cylindrical roller: 850 mm OD, 100 mm wide, Pu 315 kN, the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. The radial section height is 110.0 mm and the catalogue mass 168000 g; at 2240 kN dynamic rating this is roughly 3.56 kN of C per millimetre of bore before application factors. Fit practice for NU19-630-ECMA-HB1: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 19/630, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 19/630 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 850 mm raceway.", "The 2240/4400 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU19-630-ECMA-HB1?", "a": "SKF NU 19/630 ECMA/HB1 is a single-row caged cylindrical roller bearing with 630 mm bore, 850 mm OD and 100 mm width per ISO 15. SKF lists C 2240 kN, C0 4400 kN, Pu 315 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 168000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU19-630-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU19-630-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU19", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU19-630-ECMA-HB1", "SKF NU 19/630 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU1964-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 1964 ECMA", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 440, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 693, "static_load_kN": 1200, "fatigue_load_limit_kN": 110, "max_rpm": 2000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "weight_g": 26000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 320 mm shaft, SKF lists NU1964-ECMA as single-row caged cylindrical roller: 440 mm OD, 56 mm wide, Pu 110 kN, the catalogue lists 1,500 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 693 kN and C0 1200 kN, size the bearing on the 320×440 mm ISO 15 envelope and check the 110 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Fit practice for NU1964-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1964, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1964 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 56 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 440 mm raceway.", "The 693/1200 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1964-ECMA?", "a": "SKF NU 1964 ECMA is a single-row caged cylindrical roller bearing with 320 mm bore, 440 mm OD and 56 mm width per ISO 15. SKF lists C 693 kN, C0 1200 kN, Pu 110 kN, reference speed 1,500 r/min and limiting speed 2,000 r/min, mass about 26000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1964-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1964-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1964", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1964-ECMA", "SKF NU 1964 ECMA" ], "locale_variants": {} }, { "sku": "NU1968-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 1968 ECMA", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 460, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 682, "static_load_kN": 1200, "fatigue_load_limit_kN": 108, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 27500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 340 mm shaft, SKF lists NU1968-ECMA as single-row caged cylindrical roller: 460 mm OD, 56 mm wide, Pu 108 kN, the catalogue lists 1,400 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.76 (1200 against 682 kN), and the Pu figure 108 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,400 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Fit practice for NU1968-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1968, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1968 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 56 mm-wide ring and concentrates load.", "The 682/1200 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1968-ECMA?", "a": "SKF NU 1968 ECMA is a single-row caged cylindrical roller bearing with 340 mm bore, 460 mm OD and 56 mm width per ISO 15. SKF lists C 682 kN, C0 1200 kN, Pu 108 kN, reference speed 1,400 r/min and limiting speed 1,900 r/min, mass about 27500 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1968-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1968-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1968", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1968-ECMA", "SKF NU 1968 ECMA" ], "locale_variants": {} }, { "sku": "NU1972-ECMP", "brand": "SKF", "manufacturer_designation": "SKF NU 1972 ECMP", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 480, "B_mm": 56, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 781, "static_load_kN": 1460, "fatigue_load_limit_kN": 129, "max_rpm": 2000, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "weight_g": 29000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 1972 ECMP is a single-row caged cylindrical roller bearing sized 360×480×56 mm — a dimension series 19 (ultra-slim section for large shafts), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMP suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 781 kN and C0 1460 kN, size the bearing on the 360×480 mm ISO 15 envelope and check the 129 kN Pu against the equivalent-load floor; the catalogue lists 1,400 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 360 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1972, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1972 ECMP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 56 mm-wide ring and concentrates load.", "The 781/1460 kN ratings are SKF catalogue 17000 (2018) values for the ECMP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1972-ECMP?", "a": "SKF NU 1972 ECMP is a single-row caged cylindrical roller bearing with 360 mm bore, 480 mm OD and 56 mm width per ISO 15. SKF lists C 781 kN, C0 1460 kN, Pu 129 kN, reference speed 1,400 r/min and limiting speed 2,000 r/min, mass about 29000 g." }, { "q": "What does the NU designation and ECMP suffix mean?", "a": "The ECMP suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1972-ECMP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1972-ECMP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1972", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1972-ECMP", "SKF NU 1972 ECMP" ], "locale_variants": {} }, { "sku": "NU1988-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1988 MA", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 440, "D_mm": 600, "B_mm": 74, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 2000, "fatigue_load_limit_kN": 170, "max_rpm": 1400, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1400, "weight_g": 53000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU1988-MA is the 440 mm bore entry in the NU1900 range: a 440×600×74 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1060 kN / C0 2000 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.89 (2000 against 1060 kN), and the Pu figure 170 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 440 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1988, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1988 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 600 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 74 mm-wide ring and concentrates load.", "The 1060/2000 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1988-MA?", "a": "SKF NU 1988 MA is a single-row caged cylindrical roller bearing with 440 mm bore, 600 mm OD and 74 mm width per ISO 15. SKF lists C 1060 kN, C0 2000 kN, Pu 170 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 53000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1988-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1988-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1988", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1988-MA", "SKF NU 1988 MA" ], "locale_variants": {} }, { "sku": "NU1996-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 1996 MA", "series": "NU1900-series", "type": "cylindrical_roller", "d_mm": 480, "D_mm": 650, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1170, "static_load_kN": 2240, "fatigue_load_limit_kN": 183, "max_rpm": 1300, "reference_speed_rpm": 950, "limiting_speed_rpm": 1300, "weight_g": 76000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 1996 MA resolves to a 480×650×78 mm single-row caged cylindrical roller bearing (dimension series 19 (ultra-slim section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. With C 1170 kN and C0 2240 kN, size the bearing on the 480×650 mm ISO 15 envelope and check the 183 kN Pu against the equivalent-load floor; the catalogue lists 950 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 480 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 19 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1996, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1996 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 78 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1170/2240 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU1996-MA?", "a": "SKF NU 1996 MA is a single-row caged cylindrical roller bearing with 480 mm bore, 650 mm OD and 78 mm width per ISO 15. SKF lists C 1170 kN, C0 2240 kN, Pu 183 kN, reference speed 950 r/min and limiting speed 1,300 r/min, mass about 76000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU1996-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU1996-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU1996", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU1996-MA", "SKF NU 1996 MA" ], "locale_variants": {} }, { "sku": "NU20-500-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/500 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 720, "B_mm": 128, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2920, "static_load_kN": 5850, "fatigue_load_limit_kN": 440, "max_rpm": 1100, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "weight_g": 180000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 20/500 ECMA resolves to a 500×720×128 mm single-row caged cylindrical roller bearing (dimension series 20 (light section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 2.00 (5850 against 2920 kN), and the Pu figure 440 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 750 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 500 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/500 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 128 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2920/5850 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-500-ECMA?", "a": "SKF NU 20/500 ECMA is a single-row caged cylindrical roller bearing with 500 mm bore, 720 mm OD and 128 mm width per ISO 15. SKF lists C 2920 kN, C0 5850 kN, Pu 440 kN, reference speed 750 r/min and limiting speed 1,100 r/min, mass about 180000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-500-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-500-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-500-ECMA", "SKF NU 20/500 ECMA" ], "locale_variants": {} }, { "sku": "NU20-530-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/530 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 530, "D_mm": 780, "B_mm": 145, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3740, "static_load_kN": 7350, "fatigue_load_limit_kN": 550, "max_rpm": 1000, "reference_speed_rpm": 670, "limiting_speed_rpm": 1000, "weight_g": 253000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU20-530-ECMA is the 530 mm bore entry in the NU2000 range: a 530×780×145 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 3740 kN / C0 7350 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 125.0 mm and the catalogue mass 253000 g; at 3740 kN dynamic rating this is roughly 7.06 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/530, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/530 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 145 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 3740/7350 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-530-ECMA?", "a": "SKF NU 20/530 ECMA is a single-row caged cylindrical roller bearing with 530 mm bore, 780 mm OD and 145 mm width per ISO 15. SKF lists C 3740 kN, C0 7350 kN, Pu 550 kN, reference speed 670 r/min and limiting speed 1,000 r/min, mass about 253000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-530-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-530-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-530-ECMA", "SKF NU 20/530 ECMA" ], "locale_variants": {} }, { "sku": "NU20-560-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/560 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 560, "D_mm": 820, "B_mm": 150, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3800, "static_load_kN": 7650, "fatigue_load_limit_kN": 560, "max_rpm": 1000, "reference_speed_rpm": 630, "limiting_speed_rpm": 1000, "weight_g": 290000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 560 mm shaft, SKF lists NU20-560-ECMA as single-row caged cylindrical roller: 820 mm OD, 150 mm wide, Pu 560 kN, the catalogue lists 630 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. With C 3800 kN and C0 7650 kN, size the bearing on the 560×820 mm ISO 15 envelope and check the 560 kN Pu against the equivalent-load floor; the catalogue lists 630 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 560 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/560, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/560 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 820 mm raceway.", "The 3800/7650 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-560-ECMA?", "a": "SKF NU 20/560 ECMA is a single-row caged cylindrical roller bearing with 560 mm bore, 820 mm OD and 150 mm width per ISO 15. SKF lists C 3800 kN, C0 7650 kN, Pu 560 kN, reference speed 630 r/min and limiting speed 1,000 r/min, mass about 290000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-560-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-560-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-560-ECMA", "SKF NU 20/560 ECMA" ], "locale_variants": {} }, { "sku": "NU20-600-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/600 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 600, "D_mm": 870, "B_mm": 155, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4180, "static_load_kN": 8000, "fatigue_load_limit_kN": 570, "max_rpm": 900, "reference_speed_rpm": 600, "limiting_speed_rpm": 900, "weight_g": 325000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 20/600 ECMA is a single-row caged cylindrical roller bearing sized 600×870×155 mm — a dimension series 20 (light section for large shafts), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 135.0 mm and the catalogue mass 325000 g; at 4180 kN dynamic rating this is roughly 6.97 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/600, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/600 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 155 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 4180/8000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-600-ECMA?", "a": "SKF NU 20/600 ECMA is a single-row caged cylindrical roller bearing with 600 mm bore, 870 mm OD and 155 mm width per ISO 15. SKF lists C 4180 kN, C0 8000 kN, Pu 570 kN, reference speed 600 r/min and limiting speed 900 r/min, mass about 325000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-600-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-600-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-600-ECMA", "SKF NU 20/600 ECMA" ], "locale_variants": {} }, { "sku": "NU20-630-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/630 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 630, "D_mm": 920, "B_mm": 170, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4730, "static_load_kN": 9500, "fatigue_load_limit_kN": 670, "max_rpm": 850, "reference_speed_rpm": 560, "limiting_speed_rpm": 850, "weight_g": 400000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 20/630 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 630×920×170 mm envelope, dimension series 20 (light section for large shafts), with catalogue mass 400000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 145.0 mm and the catalogue mass 400000 g; at 4730 kN dynamic rating this is roughly 7.51 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 630 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/630, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/630 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 170 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 920 mm raceway.", "The 4730/9500 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-630-ECMA?", "a": "SKF NU 20/630 ECMA is a single-row caged cylindrical roller bearing with 630 mm bore, 920 mm OD and 170 mm width per ISO 15. SKF lists C 4730 kN, C0 9500 kN, Pu 670 kN, reference speed 560 r/min and limiting speed 850 r/min, mass about 400000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-630-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-630-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-630-ECMA", "SKF NU 20/630 ECMA" ], "locale_variants": {} }, { "sku": "NU20-710-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 20/710 ECMA/HB1", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 710, "D_mm": 1030, "B_mm": 185, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5940, "static_load_kN": 12000, "fatigue_load_limit_kN": 815, "max_rpm": 700, "reference_speed_rpm": 480, "limiting_speed_rpm": 700, "weight_g": 540000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 710 mm shaft, SKF lists NU20-710-ECMA-HB1 as single-row caged cylindrical roller: 1030 mm OD, 185 mm wide, Pu 815 kN, the catalogue lists 480 r/min thermal reference speed and 700 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 710 mm seat is about 8.37 kN/mm, typical of dimension series 20 (light section for large shafts); use C0 12000 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 710 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/710, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/710 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5940/12000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-710-ECMA-HB1?", "a": "SKF NU 20/710 ECMA/HB1 is a single-row caged cylindrical roller bearing with 710 mm bore, 1030 mm OD and 185 mm width per ISO 15. SKF lists C 5940 kN, C0 12000 kN, Pu 815 kN, reference speed 480 r/min and limiting speed 700 r/min, mass about 540000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-710-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-710-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-710-ECMA-HB1", "SKF NU 20/710 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU20-750-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/750 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 750, "D_mm": 1090, "B_mm": 195, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 7040, "static_load_kN": 14600, "fatigue_load_limit_kN": 980, "max_rpm": 670, "reference_speed_rpm": 430, "limiting_speed_rpm": 670, "weight_g": 635000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 20/750 ECMA resolves to a 750×1090×195 mm single-row caged cylindrical roller bearing (dimension series 20 (light section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 2.07 (14600 against 7040 kN), and the Pu figure 980 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 430 r/min thermal reference speed and 670 r/min mechanical limiting speed. Fit practice for NU20-750-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/750, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/750 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 195 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1090 mm raceway.", "The 7040/14600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-750-ECMA?", "a": "SKF NU 20/750 ECMA is a single-row caged cylindrical roller bearing with 750 mm bore, 1090 mm OD and 195 mm width per ISO 15. SKF lists C 7040 kN, C0 14600 kN, Pu 980 kN, reference speed 430 r/min and limiting speed 670 r/min, mass about 635000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-750-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-750-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-750-ECMA", "SKF NU 20/750 ECMA" ], "locale_variants": {} }, { "sku": "NU20-800-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/800 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 800, "D_mm": 1150, "B_mm": 200, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 7040, "static_load_kN": 14600, "fatigue_load_limit_kN": 950, "max_rpm": 630, "reference_speed_rpm": 400, "limiting_speed_rpm": 630, "weight_g": 715000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 20/800 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 800×1150×200 mm envelope, dimension series 20 (light section for large shafts), with catalogue mass 715000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 175.0 mm and the catalogue mass 715000 g; at 7040 kN dynamic rating this is roughly 8.80 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/800, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/800 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1150 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1150 mm raceway.", "The 7040/14600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-800-ECMA?", "a": "SKF NU 20/800 ECMA is a single-row caged cylindrical roller bearing with 800 mm bore, 1150 mm OD and 200 mm width per ISO 15. SKF lists C 7040 kN, C0 14600 kN, Pu 950 kN, reference speed 400 r/min and limiting speed 630 r/min, mass about 715000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-800-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-800-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-800-ECMA", "SKF NU 20/800 ECMA" ], "locale_variants": {} }, { "sku": "NU20-850-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 20/850 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 850, "D_mm": 1220, "B_mm": 212, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 8420, "static_load_kN": 18600, "fatigue_load_limit_kN": 1200, "max_rpm": 560, "reference_speed_rpm": 360, "limiting_speed_rpm": 560, "weight_g": 880000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 850 mm shaft, SKF lists NU20-850-ECMA as single-row caged cylindrical roller: 1220 mm OD, 212 mm wide, Pu 1200 kN, the catalogue lists 360 r/min thermal reference speed and 560 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 2.21 (18600 against 8420 kN), and the Pu figure 1200 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 360 r/min thermal reference speed and 560 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 20/850, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 20/850 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1220 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1220 mm raceway.", "The 8420/18600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU20-850-ECMA?", "a": "SKF NU 20/850 ECMA is a single-row caged cylindrical roller bearing with 850 mm bore, 1220 mm OD and 212 mm width per ISO 15. SKF lists C 8420 kN, C0 18600 kN, Pu 1200 kN, reference speed 360 r/min and limiting speed 560 r/min, mass about 880000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU20-850-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU20-850-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU20", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU20-850-ECMA", "SKF NU 20/850 ECMA" ], "locale_variants": {} }, { "sku": "NU202-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 202 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 15, "D_mm": 35, "B_mm": 11, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 12.5, "static_load_kN": 10.2, "fatigue_load_limit_kN": 1.22, "max_rpm": 26000, "reference_speed_rpm": 22000, "limiting_speed_rpm": 26000, "weight_g": 47, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 15 mm shaft, SKF lists NU202-ECP as single-row caged cylindrical roller: 35 mm OD, 11 mm wide, Pu 1.22 kN, the catalogue lists 22,000 r/min thermal reference speed and 26,000 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 15 mm seat is about 0.83 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 10.2 kN for static checks such as crane hook blocks standing under load. Fit practice for NU202-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 202, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 202 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 35 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 35 mm raceway.", "The 12.5/10.2 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU202-ECP?", "a": "SKF NU 202 ECP is a single-row caged cylindrical roller bearing with 15 mm bore, 35 mm OD and 11 mm width per ISO 15. SKF lists C 12.5 kN, C0 10.2 kN, Pu 1.22 kN, reference speed 22,000 r/min and limiting speed 26,000 r/min, mass about 47 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU202-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU202-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ202-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 15×35×11 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU202-ECP", "SKF NU 202 ECP" ], "locale_variants": {} }, { "sku": "NU203-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 203 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 17, "D_mm": 40, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 20, "static_load_kN": 14.3, "fatigue_load_limit_kN": 1.73, "max_rpm": 22000, "reference_speed_rpm": 20000, "limiting_speed_rpm": 22000, "weight_g": 68, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 17 mm shaft, SKF lists NU203-ECP as single-row caged cylindrical roller: 40 mm OD, 12 mm wide, Pu 1.73 kN, the catalogue lists 20,000 r/min thermal reference speed and 22,000 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 0.72 (14.3 against 20 kN), and the Pu figure 1.73 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 20,000 r/min thermal reference speed and 22,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions", "appliance and fan armature shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 203, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 203 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 12 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 40 mm raceway.", "The 20/14.3 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU203-ECP?", "a": "SKF NU 203 ECP is a single-row caged cylindrical roller bearing with 17 mm bore, 40 mm OD and 12 mm width per ISO 15. SKF lists C 20 kN, C0 14.3 kN, Pu 1.73 kN, reference speed 20,000 r/min and limiting speed 22,000 r/min, mass about 68 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU203-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU203-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU203-ECP", "SKF NU 203 ECP" ], "locale_variants": {} }, { "sku": "NU2060-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2060 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 460, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1510, "static_load_kN": 2600, "fatigue_load_limit_kN": 245, "max_rpm": 2000, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2000, "weight_g": 62000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 300 mm shaft, SKF lists NU2060-ECMA as single-row caged cylindrical roller: 460 mm OD, 95 mm wide, Pu 245 kN, the catalogue lists 1,300 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 80.0 mm and the catalogue mass 62000 g; at 1510 kN dynamic rating this is roughly 5.03 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 2060, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2060 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1510/2600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2060-ECMA?", "a": "SKF NU 2060 ECMA is a single-row caged cylindrical roller bearing with 300 mm bore, 460 mm OD and 95 mm width per ISO 15. SKF lists C 1510 kN, C0 2600 kN, Pu 245 kN, reference speed 1,300 r/min and limiting speed 2,000 r/min, mass about 62000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2060-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2060-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2060", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2060-ECMA", "SKF NU 2060 ECMA" ], "locale_variants": {} }, { "sku": "NU2088-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2088 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 440, "D_mm": 650, "B_mm": 122, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2550, "static_load_kN": 4900, "fatigue_load_limit_kN": 390, "max_rpm": 1300, "reference_speed_rpm": 8500, "limiting_speed_rpm": 1300, "weight_g": 145000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2088 ECMA is a single-row caged cylindrical roller bearing sized 440×650×122 mm — a dimension series 20 (light section for large shafts), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 105.0 mm and the catalogue mass 145000 g; at 2550 kN dynamic rating this is roughly 5.80 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 440 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 2088, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2088 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 650 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 650 mm raceway.", "The 2550/4900 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2088-ECMA?", "a": "SKF NU 2088 ECMA is a single-row caged cylindrical roller bearing with 440 mm bore, 650 mm OD and 122 mm width per ISO 15. SKF lists C 2550 kN, C0 4900 kN, Pu 390 kN, reference speed 8,500 r/min and limiting speed 1,300 r/min, mass about 145000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2088-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2088-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2088", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2088-ECMA", "SKF NU 2088 ECMA" ], "locale_variants": {} }, { "sku": "NU2096-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2096 ECMA", "series": "NU2000-series", "type": "cylindrical_roller", "d_mm": 480, "D_mm": 700, "B_mm": 128, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2860, "static_load_kN": 5600, "fatigue_load_limit_kN": 430, "max_rpm": 1200, "reference_speed_rpm": 750, "limiting_speed_rpm": 1200, "weight_g": 179000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2096 ECMA resolves to a 480×700×128 mm single-row caged cylindrical roller bearing (dimension series 20 (light section for large shafts)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 110.0 mm and the catalogue mass 179000 g; at 2860 kN dynamic rating this is roughly 5.96 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 480 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 20 (light section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 2096, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2096 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 128 mm-wide ring and concentrates load.", "The 2860/5600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2096-ECMA?", "a": "SKF NU 2096 ECMA is a single-row caged cylindrical roller bearing with 480 mm bore, 700 mm OD and 128 mm width per ISO 15. SKF lists C 2860 kN, C0 5600 kN, Pu 430 kN, reference speed 750 r/min and limiting speed 1,200 r/min, mass about 179000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2096-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2096-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2096", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2096-ECMA", "SKF NU 2096 ECMA" ], "locale_variants": {} }, { "sku": "NU22-560-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 22/560 ECMA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 560, "D_mm": 1030, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 9900, "static_load_kN": 16600, "fatigue_load_limit_kN": 1160, "max_rpm": 800, "reference_speed_rpm": 530, "limiting_speed_rpm": 800, "weight_g": 1090000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 22/560 ECMA resolves to a 560×1030×272 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 9900 kN and C0 16600 kN, size the bearing on the 560×1030 mm ISO 15 envelope and check the 1160 kN Pu against the equivalent-load floor; the catalogue lists 530 r/min thermal reference speed and 800 r/min mechanical limiting speed. Fit practice for NU22-560-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 22/560, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 22/560 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 272 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 1030 mm raceway.", "The 9900/16600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU22-560-ECMA?", "a": "SKF NU 22/560 ECMA is a single-row caged cylindrical roller bearing with 560 mm bore, 1030 mm OD and 272 mm width per ISO 15. SKF lists C 9900 kN, C0 16600 kN, Pu 1160 kN, reference speed 530 r/min and limiting speed 800 r/min, mass about 1090000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU22-560-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU22-560-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU22", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU22-560-ECMA", "SKF NU 22/560 ECMA" ], "locale_variants": {} }, { "sku": "NU2203-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2203 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 17, "D_mm": 40, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 27.5, "static_load_kN": 21.6, "fatigue_load_limit_kN": 2.65, "max_rpm": 22000, "reference_speed_rpm": 20000, "limiting_speed_rpm": 22000, "weight_g": 87, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2203-ECP is the 17 mm bore entry in the NU2200 range: a 17×40×16 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 27.5 kN / C0 21.6 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 17 mm seat is about 1.62 kN/mm, typical of dimension series 22 (light-section, wide); use C0 21.6 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2203-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2203, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2203 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 16 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 40 mm raceway.", "The 27.5/21.6 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2203-ECP?", "a": "SKF NU 2203 ECP is a single-row caged cylindrical roller bearing with 17 mm bore, 40 mm OD and 16 mm width per ISO 15. SKF lists C 27.5 kN, C0 21.6 kN, Pu 2.65 kN, reference speed 20,000 r/min and limiting speed 22,000 r/min, mass about 87 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2203-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2203-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×16 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×16 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2203-ECP", "SKF NU 2203 ECP" ], "locale_variants": {} }, { "sku": "NU2204-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2204 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 47, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 34.5, "static_load_kN": 27.5, "fatigue_load_limit_kN": 3.45, "max_rpm": 19000, "reference_speed_rpm": 17000, "limiting_speed_rpm": 19000, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2204-ECP is the 20 mm bore entry in the NU2200 range: a 20×47×18 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 34.5 kN / C0 27.5 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 0.80 (27.5 against 34.5 kN), and the Pu figure 3.45 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 17,000 r/min thermal reference speed and 19,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions", "appliance and fan armature shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2204, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2204 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 47 mm raceway.", "The 34.5/27.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2204-ECP?", "a": "SKF NU 2204 ECP is a single-row caged cylindrical roller bearing with 20 mm bore, 47 mm OD and 18 mm width per ISO 15. SKF lists C 34.5 kN, C0 27.5 kN, Pu 3.45 kN, reference speed 17,000 r/min and limiting speed 19,000 r/min, mass about 140 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2204-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2204-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2204-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×47×18 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2204-ECP", "SKF NU 2204 ECP" ], "locale_variants": {} }, { "sku": "NU221-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 221 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 105, "D_mm": 190, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 300, "static_load_kN": 315, "fatigue_load_limit_kN": 36.5, "max_rpm": 4300, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4300, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 221 ECP is a single-row caged cylindrical roller bearing sized 105×190×36 mm — a dimension series 2 (light-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.05 (315 against 300 kN), and the Pu figure 36.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,800 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 221, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 221 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 300/315 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU221-ECP?", "a": "SKF NU 221 ECP is a single-row caged cylindrical roller bearing with 105 mm bore, 190 mm OD and 36 mm width per ISO 15. SKF lists C 300 kN, C0 315 kN, Pu 36.5 kN, reference speed 3,800 r/min and limiting speed 4,300 r/min, mass about 3950 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU221-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU221-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU221", "equiv_brand": "NTN", "level": "partial", "note": "Same 105×190×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU221-ECP", "SKF NU 221 ECP" ], "locale_variants": {} }, { "sku": "NU2213-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2213 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 120, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 170, "static_load_kN": 180, "fatigue_load_limit_kN": 24, "max_rpm": 6700, "reference_speed_rpm": 6300, "limiting_speed_rpm": 6700, "weight_g": 1400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2213 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 65×120×31 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 1400 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 27.5 mm and the catalogue mass 1400 g; at 170 kN dynamic rating this is roughly 2.62 kN of C per millimetre of bore before application factors. Fit practice for NU2213-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2213, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2213 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 170/180 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2213-ECP?", "a": "SKF NU 2213 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 120 mm OD and 31 mm width per ISO 15. SKF lists C 170 kN, C0 180 kN, Pu 24 kN, reference speed 6,300 r/min and limiting speed 6,700 r/min, mass about 1400 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2213-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2213-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2213", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×120×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×31 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2213-ECP", "SKF NU 2213 ECP" ], "locale_variants": {} }, { "sku": "NU2214-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2214 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 125, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 180, "static_load_kN": 193, "fatigue_load_limit_kN": 25.5, "max_rpm": 6300, "reference_speed_rpm": 6000, "limiting_speed_rpm": 6300, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2214 ECP resolves to a 70×125×31 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 180 kN and C0 193 kN, size the bearing on the 70×125 mm ISO 15 envelope and check the 25.5 kN Pu against the equivalent-load floor; the catalogue lists 6,000 r/min thermal reference speed and 6,300 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2214, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2214 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 180/193 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2214-ECP?", "a": "SKF NU 2214 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 125 mm OD and 31 mm width per ISO 15. SKF lists C 180 kN, C0 193 kN, Pu 25.5 kN, reference speed 6,000 r/min and limiting speed 6,300 r/min, mass about 1500 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2214-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2214-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2214", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×125×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×31 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2214-ECP", "SKF NU 2214 ECP" ], "locale_variants": {} }, { "sku": "NU2215-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2215 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 130, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 186, "static_load_kN": 208, "fatigue_load_limit_kN": 27, "max_rpm": 6000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6000, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2215-ECP is the 75 mm bore entry in the NU2200 range: a 75×130×31 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 186 kN / C0 208 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 186 kN and C0 208 kN, size the bearing on the 75×130 mm ISO 15 envelope and check the 27 kN Pu against the equivalent-load floor; the catalogue lists 5,600 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. Fit practice for NU2215-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2215, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2215 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 186/208 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2215-ECP?", "a": "SKF NU 2215 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 130 mm OD and 31 mm width per ISO 15. SKF lists C 186 kN, C0 208 kN, Pu 27 kN, reference speed 5,600 r/min and limiting speed 6,000 r/min, mass about 1600 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2215-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2215-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2215", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×130×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×31 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2215-ECP", "SKF NU 2215 ECP" ], "locale_variants": {} }, { "sku": "NU2216-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2216 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 212, "static_load_kN": 245, "fatigue_load_limit_kN": 31, "max_rpm": 5600, "reference_speed_rpm": 5300, "limiting_speed_rpm": 5600, "weight_g": 1950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2216-ECP is the 80 mm bore entry in the NU2200 range: a 80×140×33 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 212 kN / C0 245 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NU2216-ECP: the catalogue lists 5,300 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. The mass entry 1950 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2216, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2216 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 212/245 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2216-ECP?", "a": "SKF NU 2216 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 140 mm OD and 33 mm width per ISO 15. SKF lists C 212 kN, C0 245 kN, Pu 31 kN, reference speed 5,300 r/min and limiting speed 5,600 r/min, mass about 1950 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2216-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2216-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2216", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×140×33 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×33 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2216-ECP", "SKF NU 2216 ECP" ], "locale_variants": {} }, { "sku": "NU2217-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2217 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 150, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 250, "static_load_kN": 280, "fatigue_load_limit_kN": 34.5, "max_rpm": 5300, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5300, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 85 mm shaft, SKF lists NU2217-ECP as single-row caged cylindrical roller: 150 mm OD, 36 mm wide, Pu 34.5 kN, the catalogue lists 4,800 r/min thermal reference speed and 5,300 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 85 mm seat is about 2.94 kN/mm, typical of dimension series 22 (light-section, wide); use C0 280 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2217-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2217, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2217 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 250/280 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2217-ECP?", "a": "SKF NU 2217 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 150 mm OD and 36 mm width per ISO 15. SKF lists C 250 kN, C0 280 kN, Pu 34.5 kN, reference speed 4,800 r/min and limiting speed 5,300 r/min, mass about 2500 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2217-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2217-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2217", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×150×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×36 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×36 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2217-ECP", "SKF NU 2217 ECP" ], "locale_variants": {} }, { "sku": "NU2218-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2218 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 160, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 280, "static_load_kN": 315, "fatigue_load_limit_kN": 39, "max_rpm": 5000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5000, "weight_g": 3150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2218 ECP is a single-row caged cylindrical roller bearing sized 90×160×40 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.13 (315 against 280 kN), and the Pu figure 39 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,500 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2218, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2218 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 280/315 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2218-ECP?", "a": "SKF NU 2218 ECP is a single-row caged cylindrical roller bearing with 90 mm bore, 160 mm OD and 40 mm width per ISO 15. SKF lists C 280 kN, C0 315 kN, Pu 39 kN, reference speed 4,500 r/min and limiting speed 5,000 r/min, mass about 3150 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2218-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2218-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2218", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×160×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×40 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2218-ECP", "SKF NU 2218 ECP" ], "locale_variants": {} }, { "sku": "NU2219-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2219 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 170, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 325, "static_load_kN": 375, "fatigue_load_limit_kN": 45.5, "max_rpm": 4800, "reference_speed_rpm": 4300, "limiting_speed_rpm": 4800, "weight_g": 3800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2219 ECP is a single-row caged cylindrical roller bearing sized 95×170×43 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 325 kN and C0 375 kN, size the bearing on the 95×170 mm ISO 15 envelope and check the 45.5 kN Pu against the equivalent-load floor; the catalogue lists 4,300 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. Fit practice for NU2219-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2219, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2219 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 325/375 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2219-ECP?", "a": "SKF NU 2219 ECP is a single-row caged cylindrical roller bearing with 95 mm bore, 170 mm OD and 43 mm width per ISO 15. SKF lists C 325 kN, C0 375 kN, Pu 45.5 kN, reference speed 4,300 r/min and limiting speed 4,800 r/min, mass about 3800 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2219-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2219-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2219", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×170×43 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×43 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×43 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2219-ECP", "SKF NU 2219 ECP" ], "locale_variants": {} }, { "sku": "NU222-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 222 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 200, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 335, "static_load_kN": 365, "fatigue_load_limit_kN": 42.5, "max_rpm": 4000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4000, "weight_g": 4700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 222 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 110×200×38 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 4700 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 45.0 mm and the catalogue mass 4700 g; at 335 kN dynamic rating this is roughly 3.05 kN of C per millimetre of bore before application factors. Fit practice for NU222-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 222, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 222 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 38 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 335/365 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU222-ECP?", "a": "SKF NU 222 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 200 mm OD and 38 mm width per ISO 15. SKF lists C 335 kN, C0 365 kN, Pu 42.5 kN, reference speed 3,600 r/min and limiting speed 4,000 r/min, mass about 4700 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU222-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU222-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU222", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×200×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU222-ECP", "SKF NU 222 ECP" ], "locale_variants": {} }, { "sku": "NU2220-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2220 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 180, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 380, "static_load_kN": 450, "fatigue_load_limit_kN": 54, "max_rpm": 4500, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4500, "weight_g": 4750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2220-ECP is the 100 mm bore entry in the NU2200 range: a 100×180×46 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 380 kN / C0 450 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NU2220-ECP: the catalogue lists 4,000 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. The mass entry 4750 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2220, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2220 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 380/450 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2220-ECP?", "a": "SKF NU 2220 ECP is a single-row caged cylindrical roller bearing with 100 mm bore, 180 mm OD and 46 mm width per ISO 15. SKF lists C 380 kN, C0 450 kN, Pu 54 kN, reference speed 4,000 r/min and limiting speed 4,500 r/min, mass about 4750 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2220-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2220-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2220", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×180×46 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×46 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2220-ECP", "SKF NU 2220 ECP" ], "locale_variants": {} }, { "sku": "NU2222-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2222 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 200, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 440, "static_load_kN": 520, "fatigue_load_limit_kN": 61, "max_rpm": 4000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4000, "weight_g": 6700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2222 ECP is a single-row caged cylindrical roller bearing sized 110×200×53 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.18 (520 against 440 kN), and the Pu figure 61 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2222, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2222 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 53 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 440/520 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2222-ECP?", "a": "SKF NU 2222 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 200 mm OD and 53 mm width per ISO 15. SKF lists C 440 kN, C0 520 kN, Pu 61 kN, reference speed 3,600 r/min and limiting speed 4,000 r/min, mass about 6700 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2222-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2222-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2222", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×200×53 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×53 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×53 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2222-ECP", "SKF NU 2222 ECP" ], "locale_variants": {} }, { "sku": "NU2224-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2224 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 215, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 520, "static_load_kN": 630, "fatigue_load_limit_kN": 72, "max_rpm": 3600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3600, "weight_g": 8200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2224 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 120×215×58 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 8200 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 520 kN and C0 630 kN, size the bearing on the 120×215 mm ISO 15 envelope and check the 72 kN Pu against the equivalent-load floor; the catalogue lists 3,400 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 120 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2224, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2224 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 520/630 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2224-ECP?", "a": "SKF NU 2224 ECP is a single-row caged cylindrical roller bearing with 120 mm bore, 215 mm OD and 58 mm width per ISO 15. SKF lists C 520 kN, C0 630 kN, Pu 72 kN, reference speed 3,400 r/min and limiting speed 3,600 r/min, mass about 8200 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2224-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2224-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2224", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×215×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2224-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×58 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2224-ECP", "SKF NU 2224 ECP" ], "locale_variants": {} }, { "sku": "NU2226-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2226 ECP", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 230, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 610, "static_load_kN": 735, "fatigue_load_limit_kN": 83, "max_rpm": 3400, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3400, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2226 ECP resolves to a 130×230×64 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.20 (735 against 610 kN), and the Pu figure 83 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,200 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2226, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2226 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "The 610/735 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2226-ECP?", "a": "SKF NU 2226 ECP is a single-row caged cylindrical roller bearing with 130 mm bore, 230 mm OD and 64 mm width per ISO 15. SKF lists C 610 kN, C0 735 kN, Pu 83 kN, reference speed 3,200 r/min and limiting speed 3,400 r/min, mass about 10000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2226-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2226-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2226", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×230×64 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2226-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×64 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×64 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2226-ECP", "SKF NU 2226 ECP" ], "locale_variants": {} }, { "sku": "NU2228-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2228 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 250, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 655, "static_load_kN": 830, "fatigue_load_limit_kN": 93, "max_rpm": 4800, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4800, "weight_g": 15000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2228 ECML resolves to a 140×250×68 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 55.0 mm and the catalogue mass 15000 g; at 655 kN dynamic rating this is roughly 4.68 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 140 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2228, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2228 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 68 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 68 mm-wide ring and concentrates load.", "The 655/830 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2228-ECML?", "a": "SKF NU 2228 ECML is a single-row caged cylindrical roller bearing with 140 mm bore, 250 mm OD and 68 mm width per ISO 15. SKF lists C 655 kN, C0 830 kN, Pu 93 kN, reference speed 2,800 r/min and limiting speed 4,800 r/min, mass about 15000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2228-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2228-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2228", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×250×68 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2228-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2228-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2228-ECML", "SKF NU 2228 ECML" ], "locale_variants": {} }, { "sku": "NU2230-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 2230 ECM", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 270, "B_mm": 73, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 735, "static_load_kN": 930, "fatigue_load_limit_kN": 100, "max_rpm": 2800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 2800, "weight_g": 18500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2230-ECM is the 150 mm bore entry in the NU2200 range: a 150×270×73 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 735 kN / C0 930 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NU2230-ECM: the catalogue lists 2,600 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. The mass entry 18500 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2230, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2230 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 735/930 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2230-ECM?", "a": "SKF NU 2230 ECM is a single-row caged cylindrical roller bearing with 150 mm bore, 270 mm OD and 73 mm width per ISO 15. SKF lists C 735 kN, C0 930 kN, Pu 100 kN, reference speed 2,600 r/min and limiting speed 2,800 r/min, mass about 18500 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2230-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2230-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2230", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×270×73 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2230-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×73 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2230-ECM", "SKF NU 2230 ECM" ], "locale_variants": {} }, { "sku": "NU2232-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2232 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 290, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 930, "static_load_kN": 1200, "fatigue_load_limit_kN": 129, "max_rpm": 4000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4000, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 160 mm shaft, SKF lists NU2232-ECML as single-row caged cylindrical roller: 290 mm OD, 80 mm wide, Pu 129 kN, the catalogue lists 2,400 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. With C 930 kN and C0 1200 kN, size the bearing on the 160×290 mm ISO 15 envelope and check the 129 kN Pu against the equivalent-load floor; the catalogue lists 2,400 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2232, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2232 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 930/1200 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2232-ECML?", "a": "SKF NU 2232 ECML is a single-row caged cylindrical roller bearing with 160 mm bore, 290 mm OD and 80 mm width per ISO 15. SKF lists C 930 kN, C0 1200 kN, Pu 129 kN, reference speed 2,400 r/min and limiting speed 4,000 r/min, mass about 23000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2232-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2232-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2232", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×290×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2232-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2232-ECML", "SKF NU 2232 ECML" ], "locale_variants": {} }, { "sku": "NU2234-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2234 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 310, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 1340, "fatigue_load_limit_kN": 140, "max_rpm": 3800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3800, "weight_g": 28000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2234 ECML denotes a single-row caged cylindrical roller bearing on the ISO 15 170×310×86 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 28000 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 170 mm seat is about 6.24 kN/mm, typical of dimension series 22 (light-section, wide); use C0 1340 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2234, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2234 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1060/1340 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2234-ECML?", "a": "SKF NU 2234 ECML is a single-row caged cylindrical roller bearing with 170 mm bore, 310 mm OD and 86 mm width per ISO 15. SKF lists C 1060 kN, C0 1340 kN, Pu 140 kN, reference speed 2,200 r/min and limiting speed 3,800 r/min, mass about 28000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2234-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2234-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2234", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×310×86 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2234-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×310×86 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2234-ECML", "SKF NU 2234 ECML" ], "locale_variants": {} }, { "sku": "NU2236-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2236 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 320, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1100, "static_load_kN": 1430, "fatigue_load_limit_kN": 146, "max_rpm": 3600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3600, "weight_g": 30000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 180 mm shaft, SKF lists NU2236-ECML as single-row caged cylindrical roller: 320 mm OD, 86 mm wide, Pu 146 kN, the catalogue lists 2,200 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. The radial section height is 70.0 mm and the catalogue mass 30000 g; at 1100 kN dynamic rating this is roughly 6.11 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 180 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2236, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2236 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1100/1430 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2236-ECML?", "a": "SKF NU 2236 ECML is a single-row caged cylindrical roller bearing with 180 mm bore, 320 mm OD and 86 mm width per ISO 15. SKF lists C 1100 kN, C0 1430 kN, Pu 146 kN, reference speed 2,200 r/min and limiting speed 3,600 r/min, mass about 30000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2236-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2236-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2236", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×320×86 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2236-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×320×86 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2236-ECML", "SKF NU 2236 ECML" ], "locale_variants": {} }, { "sku": "NU2238-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2238 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 340, "B_mm": 92, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1220, "static_load_kN": 1600, "fatigue_load_limit_kN": 160, "max_rpm": 3400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3400, "weight_g": 35500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2238 ECML denotes a single-row caged cylindrical roller bearing on the ISO 15 190×340×92 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 35500 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Speed planning for NU2238-ECML: the catalogue lists 2,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 35500 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2238, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2238 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 92 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1220/1600 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2238-ECML?", "a": "SKF NU 2238 ECML is a single-row caged cylindrical roller bearing with 190 mm bore, 340 mm OD and 92 mm width per ISO 15. SKF lists C 1220 kN, C0 1600 kN, Pu 160 kN, reference speed 2,000 r/min and limiting speed 3,400 r/min, mass about 35500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2238-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2238-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2238", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×340×92 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2238-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×92 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2238-ECML", "SKF NU 2238 ECML" ], "locale_variants": {} }, { "sku": "NU224-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 224 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 215, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 390, "static_load_kN": 430, "fatigue_load_limit_kN": 49, "max_rpm": 3600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3600, "weight_g": 5750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 224 ECP resolves to a 120×215×40 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NU224-ECP: the catalogue lists 3,400 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. The mass entry 5750 g covers the complete catalogue execution. Fit practice for NU224-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 224, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 224 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 390/430 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU224-ECP?", "a": "SKF NU 224 ECP is a single-row caged cylindrical roller bearing with 120 mm bore, 215 mm OD and 40 mm width per ISO 15. SKF lists C 390 kN, C0 430 kN, Pu 49 kN, reference speed 3,400 r/min and limiting speed 3,600 r/min, mass about 5750 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU224-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU224-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU224", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×215×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP224-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU224-ECP", "SKF NU 224 ECP" ], "locale_variants": {} }, { "sku": "NU2240-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2240 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 360, "B_mm": 98, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1370, "static_load_kN": 1800, "fatigue_load_limit_kN": 180, "max_rpm": 3200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3200, "weight_g": 44000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2240 ECML is a single-row caged cylindrical roller bearing sized 200×360×98 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1370 kN and C0 1800 kN, size the bearing on the 200×360 mm ISO 15 envelope and check the 180 kN Pu against the equivalent-load floor; the catalogue lists 1,900 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Fit practice for NU2240-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2240, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2240 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "The 1370/1800 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2240-ECML?", "a": "SKF NU 2240 ECML is a single-row caged cylindrical roller bearing with 200 mm bore, 360 mm OD and 98 mm width per ISO 15. SKF lists C 1370 kN, C0 1800 kN, Pu 180 kN, reference speed 1,900 r/min and limiting speed 3,200 r/min, mass about 44000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2240-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2240-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2240", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×360×98 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2240-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×360×98 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2240-ECML", "SKF NU 2240 ECML" ], "locale_variants": {} }, { "sku": "NU2244-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2244 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 400, "B_mm": 108, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1570, "static_load_kN": 2280, "fatigue_load_limit_kN": 212, "max_rpm": 3000, "reference_speed_rpm": 1600, "limiting_speed_rpm": 3000, "weight_g": 58000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2244 ECML is a single-row caged cylindrical roller bearing sized 220×400×108 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 90.0 mm and the catalogue mass 58000 g; at 1570 kN dynamic rating this is roughly 7.14 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2244, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2244 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1570/2280 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2244-ECML?", "a": "SKF NU 2244 ECML is a single-row caged cylindrical roller bearing with 220 mm bore, 400 mm OD and 108 mm width per ISO 15. SKF lists C 1570 kN, C0 2280 kN, Pu 212 kN, reference speed 1,600 r/min and limiting speed 3,000 r/min, mass about 58000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2244-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2244-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2244", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×400×108 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2244-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×108 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2244-ECML", "SKF NU 2244 ECML" ], "locale_variants": {} }, { "sku": "NU2248-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2248 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 440, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1450, "static_load_kN": 2360, "fatigue_load_limit_kN": 216, "max_rpm": 2200, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2200, "weight_g": 84000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 240 mm shaft, SKF lists NU2248-MA as single-row caged cylindrical roller: 440 mm OD, 120 mm wide, Pu 216 kN, the catalogue lists 1,500 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. With C 1450 kN and C0 2360 kN, size the bearing on the 240×440 mm ISO 15 envelope and check the 216 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 240 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2248, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2248 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1450/2360 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2248-MA?", "a": "SKF NU 2248 MA is a single-row caged cylindrical roller bearing with 240 mm bore, 440 mm OD and 120 mm width per ISO 15. SKF lists C 1450 kN, C0 2360 kN, Pu 216 kN, reference speed 1,500 r/min and limiting speed 2,200 r/min, mass about 84000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2248-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2248-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2248", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ2248-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×440×120 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2248-MA", "SKF NU 2248 MA" ], "locale_variants": {} }, { "sku": "NU2252-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2252 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 480, "B_mm": 130, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1790, "static_load_kN": 3000, "fatigue_load_limit_kN": 265, "max_rpm": 2000, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "weight_g": 110000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 260 mm shaft, SKF lists NU2252-MA as single-row caged cylindrical roller: 480 mm OD, 130 mm wide, Pu 265 kN, the catalogue lists 1,400 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Load-per-bore for the 260 mm seat is about 6.88 kN/mm, typical of dimension series 22 (light-section, wide); use C0 3000 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2252, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2252 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 480 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1790/3000 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2252-MA?", "a": "SKF NU 2252 MA is a single-row caged cylindrical roller bearing with 260 mm bore, 480 mm OD and 130 mm width per ISO 15. SKF lists C 1790 kN, C0 3000 kN, Pu 265 kN, reference speed 1,400 r/min and limiting speed 2,000 r/min, mass about 110000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2252-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2252-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2252", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ2252-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×480×130 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2252-MA", "SKF NU 2252 MA" ], "locale_variants": {} }, { "sku": "NU2256-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2256 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 500, "B_mm": 130, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2330, "static_load_kN": 3750, "fatigue_load_limit_kN": 320, "max_rpm": 2200, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2200, "weight_g": 115000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2256 ECML denotes a single-row caged cylindrical roller bearing on the ISO 15 280×500×130 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 115000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 280 mm seat is about 8.32 kN/mm, typical of dimension series 22 (light-section, wide); use C0 3750 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2256-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2256, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2256 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2330/3750 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2256-ECML?", "a": "SKF NU 2256 ECML is a single-row caged cylindrical roller bearing with 280 mm bore, 500 mm OD and 130 mm width per ISO 15. SKF lists C 2330 kN, C0 3750 kN, Pu 320 kN, reference speed 1,200 r/min and limiting speed 2,200 r/min, mass about 115000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2256-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2256-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2256", "equiv_brand": "NTN", "level": "partial", "note": "Same 280×500×130 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU2256", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2256-ECML", "SKF NU 2256 ECML" ], "locale_variants": {} }, { "sku": "NU226-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 226 ECP", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 230, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 415, "static_load_kN": 455, "fatigue_load_limit_kN": 51, "max_rpm": 3400, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3400, "weight_g": 6450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU226-ECP is the 130 mm bore entry in the NU200 range: a 130×230×40 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 415 kN / C0 455 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.10 (455 against 415 kN), and the Pu figure 51 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,200 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Fit practice for NU226-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 226, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 226 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "The 415/455 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU226-ECP?", "a": "SKF NU 226 ECP is a single-row caged cylindrical roller bearing with 130 mm bore, 230 mm OD and 40 mm width per ISO 15. SKF lists C 415 kN, C0 455 kN, Pu 51 kN, reference speed 3,200 r/min and limiting speed 3,400 r/min, mass about 6450 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU226-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU226-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU226", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×230×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP226-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU226-ECP", "SKF NU 226 ECP" ], "locale_variants": {} }, { "sku": "NU2260-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2260 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 540, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2090, "static_load_kN": 3450, "fatigue_load_limit_kN": 300, "max_rpm": 1800, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1800, "weight_g": 145000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2260 MA resolves to a 300×540×140 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 120.0 mm and the catalogue mass 145000 g; at 2090 kN dynamic rating this is roughly 6.97 kN of C per millimetre of bore before application factors. Fit practice for NU2260-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2260, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2260 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 540 mm raceway.", "The 2090/3450 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2260-MA?", "a": "SKF NU 2260 MA is a single-row caged cylindrical roller bearing with 300 mm bore, 540 mm OD and 140 mm width per ISO 15. SKF lists C 2090 kN, C0 3450 kN, Pu 300 kN, reference speed 1,200 r/min and limiting speed 1,800 r/min, mass about 145000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2260-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2260-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2260", "equiv_brand": "NTN", "level": "partial", "note": "Same 300×540×140 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU2260", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2260-MA", "SKF NU 2260 MA" ], "locale_variants": {} }, { "sku": "NU2264-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2264 ECML", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 580, "B_mm": 150, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3190, "static_load_kN": 5000, "fatigue_load_limit_kN": 415, "max_rpm": 1900, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1900, "weight_g": 176000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2264 ECML resolves to a 320×580×150 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 320 mm seat is about 9.97 kN/mm, typical of dimension series 22 (light-section, wide); use C0 5000 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 320 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2264, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2264 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 580 mm raceway.", "The 3190/5000 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2264-ECML?", "a": "SKF NU 2264 ECML is a single-row caged cylindrical roller bearing with 320 mm bore, 580 mm OD and 150 mm width per ISO 15. SKF lists C 3190 kN, C0 5000 kN, Pu 415 kN, reference speed 1,000 r/min and limiting speed 1,900 r/min, mass about 176000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2264-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2264-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2264", "equiv_brand": "NTN", "level": "partial", "note": "Same 320×580×150 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU2264", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2264-ECML", "SKF NU 2264 ECML" ], "locale_variants": {} }, { "sku": "NU2268-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2268 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 620, "B_mm": 165, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2640, "static_load_kN": 4500, "fatigue_load_limit_kN": 365, "max_rpm": 1500, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1500, "weight_g": 226000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2268 MA is a single-row caged cylindrical roller bearing sized 340×620×165 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Load-per-bore for the 340 mm seat is about 7.76 kN/mm, typical of dimension series 22 (light-section, wide); use C0 4500 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 340 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2268, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2268 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 620 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2640/4500 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2268-MA?", "a": "SKF NU 2268 MA is a single-row caged cylindrical roller bearing with 340 mm bore, 620 mm OD and 165 mm width per ISO 15. SKF lists C 2640 kN, C0 4500 kN, Pu 365 kN, reference speed 1,000 r/min and limiting speed 1,500 r/min, mass about 226000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2268-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2268-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2268", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2268-MA", "SKF NU 2268 MA" ], "locale_variants": {} }, { "sku": "NU2272-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2272 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 650, "B_mm": 170, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2920, "static_load_kN": 4900, "fatigue_load_limit_kN": 400, "max_rpm": 1400, "reference_speed_rpm": 950, "limiting_speed_rpm": 1400, "weight_g": 257000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2272 MA is a single-row caged cylindrical roller bearing sized 360×650×170 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The radial section height is 145.0 mm and the catalogue mass 257000 g; at 2920 kN dynamic rating this is roughly 8.11 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2272, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2272 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2920/4900 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2272-MA?", "a": "SKF NU 2272 MA is a single-row caged cylindrical roller bearing with 360 mm bore, 650 mm OD and 170 mm width per ISO 15. SKF lists C 2920 kN, C0 4900 kN, Pu 400 kN, reference speed 950 r/min and limiting speed 1,400 r/min, mass about 257000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2272-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2272-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2272", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2272-MA", "SKF NU 2272 MA" ], "locale_variants": {} }, { "sku": "NU2276-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2276 ECMA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 680, "B_mm": 175, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3960, "static_load_kN": 6400, "fatigue_load_limit_kN": 510, "max_rpm": 1300, "reference_speed_rpm": 850, "limiting_speed_rpm": 1300, "weight_g": 288000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2276 ECMA is a single-row caged cylindrical roller bearing sized 380×680×175 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU2276-ECMA: the catalogue lists 850 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. The mass entry 288000 g covers the complete catalogue execution. Fit practice for NU2276-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2276, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2276 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 175 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 3960/6400 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2276-ECMA?", "a": "SKF NU 2276 ECMA is a single-row caged cylindrical roller bearing with 380 mm bore, 680 mm OD and 175 mm width per ISO 15. SKF lists C 3960 kN, C0 6400 kN, Pu 510 kN, reference speed 850 r/min and limiting speed 1,300 r/min, mass about 288000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2276-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2276-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2276", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2276-ECMA", "SKF NU 2276 ECMA" ], "locale_variants": {} }, { "sku": "NU228-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 228 ECM", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 250, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 450, "static_load_kN": 510, "fatigue_load_limit_kN": 57, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 9400, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 228 ECM denotes a single-row caged cylindrical roller bearing on the ISO 15 140×250×42 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 9400 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU228-ECM: the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. The mass entry 9400 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 228, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 228 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 250 mm raceway.", "The 450/510 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU228-ECM?", "a": "SKF NU 228 ECM is a single-row caged cylindrical roller bearing with 140 mm bore, 250 mm OD and 42 mm width per ISO 15. SKF lists C 450 kN, C0 510 kN, Pu 57 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 9400 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU228-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU228-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU228", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×250×42 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ228-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×42 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP228-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×42 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU228-ECM", "SKF NU 228 ECM" ], "locale_variants": {} }, { "sku": "NU2292-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2292 MA", "series": "NU2200-series", "type": "cylindrical_roller", "d_mm": 460, "D_mm": 830, "B_mm": 212, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5120, "static_load_kN": 8650, "fatigue_load_limit_kN": 655, "max_rpm": 1100, "reference_speed_rpm": 700, "limiting_speed_rpm": 1100, "weight_g": 527000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2292 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 460×830×212 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 527000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NU2292-MA: the catalogue lists 700 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. The mass entry 527000 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2292, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2292 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 212 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5120/8650 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2292-MA?", "a": "SKF NU 2292 MA is a single-row caged cylindrical roller bearing with 460 mm bore, 830 mm OD and 212 mm width per ISO 15. SKF lists C 5120 kN, C0 8650 kN, Pu 655 kN, reference speed 700 r/min and limiting speed 1,100 r/min, mass about 527000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2292-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2292-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2292", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2292-MA", "SKF NU 2292 MA" ], "locale_variants": {} }, { "sku": "NU230-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 230 ECM", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 270, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 510, "static_load_kN": 600, "fatigue_load_limit_kN": 64, "max_rpm": 2800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 2800, "weight_g": 11500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 230 ECM is a single-row caged cylindrical roller bearing sized 150×270×45 mm — a dimension series 2 (light-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.18 (600 against 510 kN), and the Pu figure 64 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,600 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 230, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 230 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "The 510/600 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU230-ECM?", "a": "SKF NU 230 ECM is a single-row caged cylindrical roller bearing with 150 mm bore, 270 mm OD and 45 mm width per ISO 15. SKF lists C 510 kN, C0 600 kN, Pu 64 kN, reference speed 2,600 r/min and limiting speed 2,800 r/min, mass about 11500 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU230-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU230-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU230", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×270×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ230-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×45 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP230-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×45 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU230-ECM", "SKF NU 230 ECM" ], "locale_variants": {} }, { "sku": "NU2304-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2304 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 52, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 47.5, "static_load_kN": 38, "fatigue_load_limit_kN": 4.8, "max_rpm": 18000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 18000, "weight_g": 210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2304 ECP resolves to a 20×52×21 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 47.5 kN and C0 38 kN, size the bearing on the 20×52 mm ISO 15 envelope and check the 4.8 kN Pu against the equivalent-load floor; the catalogue lists 15,000 r/min thermal reference speed and 18,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2304, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2304 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 21 mm-wide ring and concentrates load.", "The 47.5/38 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2304-ECP?", "a": "SKF NU 2304 ECP is a single-row caged cylindrical roller bearing with 20 mm bore, 52 mm OD and 21 mm width per ISO 15. SKF lists C 47.5 kN, C0 38 kN, Pu 4.8 kN, reference speed 15,000 r/min and limiting speed 18,000 r/min, mass about 210 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2304-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2304-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×21 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×21 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2304-ECP", "SKF NU 2304 ECP" ], "locale_variants": {} }, { "sku": "NU2313-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2313 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 140, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 285, "static_load_kN": 290, "fatigue_load_limit_kN": 38, "max_rpm": 6000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6000, "weight_g": 3200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2313 ECP is a single-row caged cylindrical roller bearing sized 65×140×48 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 285 kN and C0 290 kN, size the bearing on the 65×140 mm ISO 15 envelope and check the 38 kN Pu against the equivalent-load floor; the catalogue lists 5,300 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 65 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2313, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2313 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "The 285/290 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2313-ECP?", "a": "SKF NU 2313 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 140 mm OD and 48 mm width per ISO 15. SKF lists C 285 kN, C0 290 kN, Pu 38 kN, reference speed 5,300 r/min and limiting speed 6,000 r/min, mass about 3200 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2313-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2313-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2313", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×140×48 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×48 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×48 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2313-ECP", "SKF NU 2313 ECP" ], "locale_variants": {} }, { "sku": "NU2314-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2314 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 150, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 315, "static_load_kN": 325, "fatigue_load_limit_kN": 41.5, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 3950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2314 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 70×150×51 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 3950 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NU2314-ECP: the catalogue lists 4,800 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. The mass entry 3950 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2314, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2314 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "The 315/325 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2314-ECP?", "a": "SKF NU 2314 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 150 mm OD and 51 mm width per ISO 15. SKF lists C 315 kN, C0 325 kN, Pu 41.5 kN, reference speed 4,800 r/min and limiting speed 5,600 r/min, mass about 3950 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2314-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2314-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2314", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×150×51 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×51 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×51 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2314-ECP", "SKF NU 2314 ECP" ], "locale_variants": {} }, { "sku": "NU2315-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2315 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 160, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 380, "static_load_kN": 400, "fatigue_load_limit_kN": 50, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 4800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2315 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 75×160×55 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 4800 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 75 mm seat is about 5.07 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 400 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 75 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2315, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2315 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 55 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 160 mm raceway.", "The 380/400 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2315-ECP?", "a": "SKF NU 2315 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 160 mm OD and 55 mm width per ISO 15. SKF lists C 380 kN, C0 400 kN, Pu 50 kN, reference speed 4,500 r/min and limiting speed 5,300 r/min, mass about 4800 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2315-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2315-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2315", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×160×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×55 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2315-ECP", "SKF NU 2315 ECP" ], "locale_variants": {} }, { "sku": "NU2316-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2316 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 170, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 415, "static_load_kN": 440, "fatigue_load_limit_kN": 55, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 5750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2316 ECP resolves to a 80×170×58 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.06 (440 against 415 kN), and the Pu figure 55 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,300 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2316, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2316 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "The 415/440 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2316-ECP?", "a": "SKF NU 2316 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 170 mm OD and 58 mm width per ISO 15. SKF lists C 415 kN, C0 440 kN, Pu 55 kN, reference speed 4,300 r/min and limiting speed 5,000 r/min, mass about 5750 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2316-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2316-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2316", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×170×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×58 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2316-ECP", "SKF NU 2316 ECP" ], "locale_variants": {} }, { "sku": "NU2317-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2317 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 180, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 455, "static_load_kN": 490, "fatigue_load_limit_kN": 60, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800, "weight_g": 6850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2317-ECP is the 85 mm bore entry in the NU2300 range: a 85×180×60 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 455 kN / C0 490 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 47.5 mm and the catalogue mass 6850 g; at 455 kN dynamic rating this is roughly 5.35 kN of C per millimetre of bore before application factors. Fit practice for NU2317-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2317, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2317 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 455/490 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2317-ECP?", "a": "SKF NU 2317 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 180 mm OD and 60 mm width per ISO 15. SKF lists C 455 kN, C0 490 kN, Pu 60 kN, reference speed 4,000 r/min and limiting speed 4,800 r/min, mass about 6850 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2317-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2317-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2317", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×180×60 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×60 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×60 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2317-ECP", "SKF NU 2317 ECP" ], "locale_variants": {} }, { "sku": "NU2318-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2318 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 190, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 500, "static_load_kN": 540, "fatigue_load_limit_kN": 65.5, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 8000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2318-ECP is the 90 mm bore entry in the NU2300 range: a 90×190×64 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 500 kN / C0 540 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 500 kN and C0 540 kN, size the bearing on the 90×190 mm ISO 15 envelope and check the 65.5 kN Pu against the equivalent-load floor; the catalogue lists 3,800 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2318, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2318 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 64 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 500/540 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2318-ECP?", "a": "SKF NU 2318 ECP is a single-row caged cylindrical roller bearing with 90 mm bore, 190 mm OD and 64 mm width per ISO 15. SKF lists C 500 kN, C0 540 kN, Pu 65.5 kN, reference speed 3,800 r/min and limiting speed 4,500 r/min, mass about 8000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2318-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2318-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2318", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×190×64 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×64 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×64 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2318-ECP", "SKF NU 2318 ECP" ], "locale_variants": {} }, { "sku": "NU2319-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2319 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 200, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 530, "static_load_kN": 585, "fatigue_load_limit_kN": 69.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 9350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 95 mm shaft, SKF lists NU2319-ECP as single-row caged cylindrical roller: 200 mm OD, 67 mm wide, Pu 69.5 kN, the catalogue lists 3,600 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 95 mm seat is about 5.58 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 585 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2319-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2319, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2319 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 530/585 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2319-ECP?", "a": "SKF NU 2319 ECP is a single-row caged cylindrical roller bearing with 95 mm bore, 200 mm OD and 67 mm width per ISO 15. SKF lists C 530 kN, C0 585 kN, Pu 69.5 kN, reference speed 3,600 r/min and limiting speed 4,300 r/min, mass about 9350 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2319-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2319-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2319", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×200×67 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2319-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×67 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2319-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×67 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2319-ECP", "SKF NU 2319 ECP" ], "locale_variants": {} }, { "sku": "NU232-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 232 ECM", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 290, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 585, "static_load_kN": 680, "fatigue_load_limit_kN": 72, "max_rpm": 2600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2600, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 232 ECM denotes a single-row caged cylindrical roller bearing on the ISO 15 160×290×48 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 14000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 585 kN and C0 680 kN, size the bearing on the 160×290 mm ISO 15 envelope and check the 72 kN Pu against the equivalent-load floor; the catalogue lists 2,400 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 232, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 232 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 48 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 48 mm-wide ring and concentrates load.", "The 585/680 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU232-ECM?", "a": "SKF NU 232 ECM is a single-row caged cylindrical roller bearing with 160 mm bore, 290 mm OD and 48 mm width per ISO 15. SKF lists C 585 kN, C0 680 kN, Pu 72 kN, reference speed 2,400 r/min and limiting speed 2,600 r/min, mass about 14000 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU232-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU232-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU232", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×290×48 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ232-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×48 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP232-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×48 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU232-ECM", "SKF NU 232 ECM" ], "locale_variants": {} }, { "sku": "NU2320-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2320 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 215, "B_mm": 73, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 670, "static_load_kN": 735, "fatigue_load_limit_kN": 85, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 12000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2320 ECP resolves to a 100×215×73 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.10 (735 against 670 kN), and the Pu figure 85 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,200 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2320, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2320 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 73 mm-wide ring and concentrates load.", "The 670/735 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2320-ECP?", "a": "SKF NU 2320 ECP is a single-row caged cylindrical roller bearing with 100 mm bore, 215 mm OD and 73 mm width per ISO 15. SKF lists C 670 kN, C0 735 kN, Pu 85 kN, reference speed 3,200 r/min and limiting speed 3,800 r/min, mass about 12000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2320-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2320-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2320", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×215×73 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2320-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×73 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2320-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×73 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2320-ECP", "SKF NU 2320 ECP" ], "locale_variants": {} }, { "sku": "NU2322-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 2322 ECP", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 240, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 780, "static_load_kN": 900, "fatigue_load_limit_kN": 102, "max_rpm": 3400, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3400, "weight_g": 17000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2322-ECP is the 110 mm bore entry in the NU2300 range: a 110×240×80 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 780 kN / C0 900 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 780 kN and C0 900 kN, size the bearing on the 110×240 mm ISO 15 envelope and check the 102 kN Pu against the equivalent-load floor; the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2322, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2322 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 780/900 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2322-ECP?", "a": "SKF NU 2322 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 240 mm OD and 80 mm width per ISO 15. SKF lists C 780 kN, C0 900 kN, Pu 102 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 17000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2322-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2322-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2322", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×240×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×80 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2322-ECP", "SKF NU 2322 ECP" ], "locale_variants": {} }, { "sku": "NU2324-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2324 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 260, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 915, "static_load_kN": 1040, "fatigue_load_limit_kN": 116, "max_rpm": 5000, "reference_speed_rpm": 2800, "limiting_speed_rpm": 5000, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2324 ECML denotes a single-row caged cylindrical roller bearing on the ISO 15 120×260×86 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 22500 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 915 kN and C0 1040 kN, size the bearing on the 120×260 mm ISO 15 envelope and check the 116 kN Pu against the equivalent-load floor; the catalogue lists 2,800 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2324, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2324 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 86 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 86 mm-wide ring and concentrates load.", "The 915/1040 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2324-ECML?", "a": "SKF NU 2324 ECML is a single-row caged cylindrical roller bearing with 120 mm bore, 260 mm OD and 86 mm width per ISO 15. SKF lists C 915 kN, C0 1040 kN, Pu 116 kN, reference speed 2,800 r/min and limiting speed 5,000 r/min, mass about 22500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2324-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2324-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2324", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×260×86 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2324-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×86 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2324-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×86 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2324-ECML", "SKF NU 2324 ECML" ], "locale_variants": {} }, { "sku": "NU2326-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2326 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 280, "B_mm": 93, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 1250, "fatigue_load_limit_kN": 137, "max_rpm": 4500, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4500, "weight_g": 28500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2326-ECML is the 130 mm bore entry in the NU2300 range: a 130×280×93 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1060 kN / C0 1250 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Load-per-bore for the 130 mm seat is about 8.15 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 1250 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2326, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2326 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 93 mm-wide ring and concentrates load.", "The 1060/1250 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2326-ECML?", "a": "SKF NU 2326 ECML is a single-row caged cylindrical roller bearing with 130 mm bore, 280 mm OD and 93 mm width per ISO 15. SKF lists C 1060 kN, C0 1250 kN, Pu 137 kN, reference speed 2,400 r/min and limiting speed 4,500 r/min, mass about 28500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2326-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2326-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2326", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×280×93 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2326-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×93 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2326-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×93 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2326-ECML", "SKF NU 2326 ECML" ], "locale_variants": {} }, { "sku": "NU2328-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2328 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 300, "B_mm": 102, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1200, "static_load_kN": 1430, "fatigue_load_limit_kN": 150, "max_rpm": 4300, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4300, "weight_g": 36000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2328 ECML is a single-row caged cylindrical roller bearing sized 140×300×102 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.19 (1430 against 1200 kN), and the Pu figure 150 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,400 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. Fit practice for NU2328-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2328, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2328 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 300 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1200/1430 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2328-ECML?", "a": "SKF NU 2328 ECML is a single-row caged cylindrical roller bearing with 140 mm bore, 300 mm OD and 102 mm width per ISO 15. SKF lists C 1200 kN, C0 1430 kN, Pu 150 kN, reference speed 2,400 r/min and limiting speed 4,300 r/min, mass about 36000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2328-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2328-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2328", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×300×102 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2328-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×102 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP2328-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×102 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2328-ECML", "SKF NU 2328 ECML" ], "locale_variants": {} }, { "sku": "NU2330-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2330 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 320, "B_mm": 108, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1370, "static_load_kN": 1630, "fatigue_load_limit_kN": 170, "max_rpm": 4000, "reference_speed_rpm": 2200, "limiting_speed_rpm": 4000, "weight_g": 42500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2330 ECML is a single-row caged cylindrical roller bearing sized 150×320×108 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.19 (1630 against 1370 kN), and the Pu figure 170 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,200 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Fit practice for NU2330-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2330, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2330 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1370/1630 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2330-ECML?", "a": "SKF NU 2330 ECML is a single-row caged cylindrical roller bearing with 150 mm bore, 320 mm OD and 108 mm width per ISO 15. SKF lists C 1370 kN, C0 1630 kN, Pu 170 kN, reference speed 2,200 r/min and limiting speed 4,000 r/min, mass about 42500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2330-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2330-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2330", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×320×108 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2330-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×320×108 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2330-ECML", "SKF NU 2330 ECML" ], "locale_variants": {} }, { "sku": "NU2332-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2332 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 340, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1250, "static_load_kN": 1730, "fatigue_load_limit_kN": 173, "max_rpm": 3600, "reference_speed_rpm": 1800, "limiting_speed_rpm": 3600, "weight_g": 50000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2332 ECML resolves to a 160×340×114 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1250 kN and C0 1730 kN, size the bearing on the 160×340 mm ISO 15 envelope and check the 173 kN Pu against the equivalent-load floor; the catalogue lists 1,800 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Fit practice for NU2332-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2332, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2332 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 340 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1250/1730 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2332-ECML?", "a": "SKF NU 2332 ECML is a single-row caged cylindrical roller bearing with 160 mm bore, 340 mm OD and 114 mm width per ISO 15. SKF lists C 1250 kN, C0 1730 kN, Pu 173 kN, reference speed 1,800 r/min and limiting speed 3,600 r/min, mass about 50000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2332-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2332-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2332", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×340×114 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2332-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×340×114 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2332-ECML", "SKF NU 2332 ECML" ], "locale_variants": {} }, { "sku": "NU2334-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2334 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 360, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1450, "static_load_kN": 2040, "fatigue_load_limit_kN": 204, "max_rpm": 3400, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3400, "weight_g": 60500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 170 mm shaft, SKF lists NU2334-ECML as single-row caged cylindrical roller: 360 mm OD, 120 mm wide, Pu 204 kN, the catalogue lists 1,700 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 170 mm seat is about 8.53 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 2040 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2334-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2334, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2334 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1450/2040 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2334-ECML?", "a": "SKF NU 2334 ECML is a single-row caged cylindrical roller bearing with 170 mm bore, 360 mm OD and 120 mm width per ISO 15. SKF lists C 1450 kN, C0 2040 kN, Pu 204 kN, reference speed 1,700 r/min and limiting speed 3,400 r/min, mass about 60500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2334-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2334-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2334", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×360×120 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2334-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×360×120 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2334-ECML", "SKF NU 2334 ECML" ], "locale_variants": {} }, { "sku": "NU2336-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2336 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 380, "B_mm": 126, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1610, "static_load_kN": 2240, "fatigue_load_limit_kN": 216, "max_rpm": 3200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 3200, "weight_g": 69500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2336 ECML resolves to a 180×380×126 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.39 (2240 against 1610 kN), and the Pu figure 216 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Fit practice for NU2336-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2336, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2336 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "The 1610/2240 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2336-ECML?", "a": "SKF NU 2336 ECML is a single-row caged cylindrical roller bearing with 180 mm bore, 380 mm OD and 126 mm width per ISO 15. SKF lists C 1610 kN, C0 2240 kN, Pu 216 kN, reference speed 1,600 r/min and limiting speed 3,200 r/min, mass about 69500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2336-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2336-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2336", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×380×126 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2336-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×380×126 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2336-ECML", "SKF NU 2336 ECML" ], "locale_variants": {} }, { "sku": "NU2338-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2338 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 400, "B_mm": 132, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1830, "static_load_kN": 2550, "fatigue_load_limit_kN": 236, "max_rpm": 3000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 3000, "weight_g": 80500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 190 mm shaft, SKF lists NU2338-ECML as single-row caged cylindrical roller: 400 mm OD, 132 mm wide, Pu 236 kN, the catalogue lists 1,500 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1830 kN and C0 2550 kN, size the bearing on the 190×400 mm ISO 15 envelope and check the 236 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. Fit practice for NU2338-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2338, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2338 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1830/2550 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2338-ECML?", "a": "SKF NU 2338 ECML is a single-row caged cylindrical roller bearing with 190 mm bore, 400 mm OD and 132 mm width per ISO 15. SKF lists C 1830 kN, C0 2550 kN, Pu 236 kN, reference speed 1,500 r/min and limiting speed 3,000 r/min, mass about 80500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2338-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2338-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2338", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×400×132 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2338-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×400×132 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2338-ECML", "SKF NU 2338 ECML" ], "locale_variants": {} }, { "sku": "NU234-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 234 ECML", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 310, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 695, "static_load_kN": 815, "fatigue_load_limit_kN": 85, "max_rpm": 3800, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3800, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU234-ECML is the 170 mm bore entry in the NU200 range: a 170×310×52 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 695 kN / C0 815 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.17 (815 against 695 kN), and the Pu figure 85 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,200 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Fit practice for NU234-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 234, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 234 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 310 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 695/815 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU234-ECML?", "a": "SKF NU 234 ECML is a single-row caged cylindrical roller bearing with 170 mm bore, 310 mm OD and 52 mm width per ISO 15. SKF lists C 695 kN, C0 815 kN, Pu 85 kN, reference speed 2,200 r/min and limiting speed 3,800 r/min, mass about 17500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU234-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU234-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU234", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×310×52 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ234-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×310×52 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU234-ECML", "SKF NU 234 ECML" ], "locale_variants": {} }, { "sku": "NU2340-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2340 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 420, "B_mm": 138, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1980, "static_load_kN": 2800, "fatigue_load_limit_kN": 255, "max_rpm": 2800, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "weight_g": 92500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2340-ECML is the 200 mm bore entry in the NU2300 range: a 200×420×138 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1980 kN / C0 2800 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NU2340-ECML: the catalogue lists 1,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. The mass entry 92500 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2340, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2340 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "The 1980/2800 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2340-ECML?", "a": "SKF NU 2340 ECML is a single-row caged cylindrical roller bearing with 200 mm bore, 420 mm OD and 138 mm width per ISO 15. SKF lists C 1980 kN, C0 2800 kN, Pu 255 kN, reference speed 1,400 r/min and limiting speed 2,800 r/min, mass about 92500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2340-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2340-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2340", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×420×138 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2340-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×420×138 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2340-ECML", "SKF NU 2340 ECML" ], "locale_variants": {} }, { "sku": "NU2344-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2344 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 460, "B_mm": 145, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2380, "static_load_kN": 3450, "fatigue_load_limit_kN": 310, "max_rpm": 2600, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2600, "weight_g": 118000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2344-ECML is the 220 mm bore entry in the NU2300 range: a 220×460×145 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 2380 kN / C0 3450 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 120.0 mm and the catalogue mass 118000 g; at 2380 kN dynamic rating this is roughly 10.82 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2344, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2344 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 145 mm-wide ring and concentrates load.", "The 2380/3450 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2344-ECML?", "a": "SKF NU 2344 ECML is a single-row caged cylindrical roller bearing with 220 mm bore, 460 mm OD and 145 mm width per ISO 15. SKF lists C 2380 kN, C0 3450 kN, Pu 310 kN, reference speed 1,300 r/min and limiting speed 2,600 r/min, mass about 118000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2344-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2344-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2344", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×460×145 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU2344", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2344-ECML", "SKF NU 2344 ECML" ], "locale_variants": {} }, { "sku": "NU2348-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2348 ECML", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 500, "B_mm": 155, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2750, "static_load_kN": 4000, "fatigue_load_limit_kN": 345, "max_rpm": 2400, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2400, "weight_g": 137000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2348-ECML is the 240 mm bore entry in the NU2300 range: a 240×500×155 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 2750 kN / C0 4000 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 240 mm seat is about 11.46 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 4000 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2348-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2348, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2348 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 155 mm-wide ring and concentrates load.", "The 2750/4000 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2348-ECML?", "a": "SKF NU 2348 ECML is a single-row caged cylindrical roller bearing with 240 mm bore, 500 mm OD and 155 mm width per ISO 15. SKF lists C 2750 kN, C0 4000 kN, Pu 345 kN, reference speed 1,200 r/min and limiting speed 2,400 r/min, mass about 137000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2348-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2348-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2348", "equiv_brand": "NTN", "level": "partial", "note": "Same 240×500×155 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU2348", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2348-ECML", "SKF NU 2348 ECML" ], "locale_variants": {} }, { "sku": "NU2352-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2352 ECMA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 540, "B_mm": 165, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3190, "static_load_kN": 4550, "fatigue_load_limit_kN": 400, "max_rpm": 1800, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1800, "weight_g": 193000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2352 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 260×540×165 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 193000 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 140.0 mm and the catalogue mass 193000 g; at 3190 kN dynamic rating this is roughly 12.27 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 260 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2352, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2352 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 540 mm raceway.", "The 3190/4550 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2352-ECMA?", "a": "SKF NU 2352 ECMA is a single-row caged cylindrical roller bearing with 260 mm bore, 540 mm OD and 165 mm width per ISO 15. SKF lists C 3190 kN, C0 4550 kN, Pu 400 kN, reference speed 1,100 r/min and limiting speed 1,800 r/min, mass about 193000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2352-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2352-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2352", "equiv_brand": "NTN", "level": "partial", "note": "Same 260×540×165 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2352-ECMA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×540×165 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2352-ECMA", "SKF NU 2352 ECMA" ], "locale_variants": {} }, { "sku": "NU2356-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 2356 MA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 580, "B_mm": 175, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2700, "static_load_kN": 4300, "fatigue_load_limit_kN": 365, "max_rpm": 1700, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1700, "weight_g": 230000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 2356 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 280×580×175 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 230000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Load-per-bore for the 280 mm seat is about 9.64 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 4300 kN for static checks such as crane hook blocks standing under load. Fit practice for NU2356-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2356, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2356 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 580 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 580 mm raceway.", "The 2700/4300 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2356-MA?", "a": "SKF NU 2356 MA is a single-row caged cylindrical roller bearing with 280 mm bore, 580 mm OD and 175 mm width per ISO 15. SKF lists C 2700 kN, C0 4300 kN, Pu 365 kN, reference speed 1,000 r/min and limiting speed 1,700 r/min, mass about 230000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2356-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2356-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2356", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU2356", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2356-MA", "SKF NU 2356 MA" ], "locale_variants": {} }, { "sku": "NU236-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 236 ECML", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 320, "B_mm": 52, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 720, "static_load_kN": 850, "fatigue_load_limit_kN": 88, "max_rpm": 3600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 3600, "weight_g": 18500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 236 ECML is a single-row caged cylindrical roller bearing sized 180×320×52 mm — a dimension series 2 (light-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 720 kN and C0 850 kN, size the bearing on the 180×320 mm ISO 15 envelope and check the 88 kN Pu against the equivalent-load floor; the catalogue lists 2,200 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Fit practice for NU236-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 236, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 236 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 52 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 720/850 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU236-ECML?", "a": "SKF NU 236 ECML is a single-row caged cylindrical roller bearing with 180 mm bore, 320 mm OD and 52 mm width per ISO 15. SKF lists C 720 kN, C0 850 kN, Pu 88 kN, reference speed 2,200 r/min and limiting speed 3,600 r/min, mass about 18500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU236-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU236-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU236", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×320×52 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ236-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×320×52 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU236-ECML", "SKF NU 236 ECML" ], "locale_variants": {} }, { "sku": "NU2360-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2360 ECMA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 620, "B_mm": 185, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4020, "static_load_kN": 5850, "fatigue_load_limit_kN": 480, "max_rpm": 1600, "reference_speed_rpm": 950, "limiting_speed_rpm": 1600, "weight_g": 270000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU2360-ECMA is the 300 mm bore entry in the NU2300 range: a 300×620×185 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 4020 kN / C0 5850 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 160.0 mm and the catalogue mass 270000 g; at 4020 kN dynamic rating this is roughly 13.40 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 300 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2360, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2360 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 185 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 185 mm-wide ring and concentrates load.", "The 4020/5850 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2360-ECMA?", "a": "SKF NU 2360 ECMA is a single-row caged cylindrical roller bearing with 300 mm bore, 620 mm OD and 185 mm width per ISO 15. SKF lists C 4020 kN, C0 5850 kN, Pu 480 kN, reference speed 950 r/min and limiting speed 1,600 r/min, mass about 270000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2360-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2360-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2360", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2360-ECMA", "SKF NU 2360 ECMA" ], "locale_variants": {} }, { "sku": "NU2364-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2364 ECMA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 670, "B_mm": 200, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4730, "static_load_kN": 7500, "fatigue_load_limit_kN": 600, "max_rpm": 1500, "reference_speed_rpm": 850, "limiting_speed_rpm": 1500, "weight_g": 370000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2364 ECMA resolves to a 320×670×200 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.59 (7500 against 4730 kN), and the Pu figure 600 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 850 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 320 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2364, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2364 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 670 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 200 mm-wide ring and concentrates load.", "The 4730/7500 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2364-ECMA?", "a": "SKF NU 2364 ECMA is a single-row caged cylindrical roller bearing with 320 mm bore, 670 mm OD and 200 mm width per ISO 15. SKF lists C 4730 kN, C0 7500 kN, Pu 600 kN, reference speed 850 r/min and limiting speed 1,500 r/min, mass about 370000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2364-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2364-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2364", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2364-ECMA", "SKF NU 2364 ECMA" ], "locale_variants": {} }, { "sku": "NU2368-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2368 ECMA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 710, "B_mm": 212, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5610, "static_load_kN": 8650, "fatigue_load_limit_kN": 680, "max_rpm": 1400, "reference_speed_rpm": 800, "limiting_speed_rpm": 1400, "weight_g": 439000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2368 ECMA resolves to a 340×710×212 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Speed planning for NU2368-ECMA: the catalogue lists 800 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. The mass entry 439000 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 340 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2368, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2368 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5610/8650 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2368-ECMA?", "a": "SKF NU 2368 ECMA is a single-row caged cylindrical roller bearing with 340 mm bore, 710 mm OD and 212 mm width per ISO 15. SKF lists C 5610 kN, C0 8650 kN, Pu 680 kN, reference speed 800 r/min and limiting speed 1,400 r/min, mass about 439000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2368-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2368-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2368", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2368-ECMA", "SKF NU 2368 ECMA" ], "locale_variants": {} }, { "sku": "NU2372-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2372 ECMA", "series": "NU2300-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 750, "B_mm": 224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5010, "static_load_kN": 8150, "fatigue_load_limit_kN": 630, "max_rpm": 1300, "reference_speed_rpm": 850, "limiting_speed_rpm": 1300, "weight_g": 510000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 360 mm shaft, SKF lists NU2372-ECMA as single-row caged cylindrical roller: 750 mm OD, 224 mm wide, Pu 630 kN, the catalogue lists 850 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.63 (8150 against 5010 kN), and the Pu figure 630 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 850 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 360 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2372, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2372 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5010/8150 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2372-ECMA?", "a": "SKF NU 2372 ECMA is a single-row caged cylindrical roller bearing with 360 mm bore, 750 mm OD and 224 mm width per ISO 15. SKF lists C 5010 kN, C0 8150 kN, Pu 630 kN, reference speed 850 r/min and limiting speed 1,300 r/min, mass about 510000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2372-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2372-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2372", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2372-ECMA", "SKF NU 2372 ECMA" ], "locale_variants": {} }, { "sku": "NU238-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 238 ECML", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 340, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 800, "static_load_kN": 965, "fatigue_load_limit_kN": 98, "max_rpm": 3400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3400, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU238-ECML is the 190 mm bore entry in the NU200 range: a 190×340×55 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 800 kN / C0 965 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NU238-ECML: the catalogue lists 2,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 22500 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 238, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 238 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 55 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 800/965 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU238-ECML?", "a": "SKF NU 238 ECML is a single-row caged cylindrical roller bearing with 190 mm bore, 340 mm OD and 55 mm width per ISO 15. SKF lists C 800 kN, C0 965 kN, Pu 98 kN, reference speed 2,000 r/min and limiting speed 3,400 r/min, mass about 22500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU238-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU238-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU238", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×340×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ238-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP238-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×55 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU238-ECML", "SKF NU 238 ECML" ], "locale_variants": {} }, { "sku": "NU240-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 240 ECML", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 360, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 880, "static_load_kN": 1060, "fatigue_load_limit_kN": 106, "max_rpm": 3200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 3200, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 240 ECML resolves to a 200×360×58 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 200 mm seat is about 4.40 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 1060 kN for static checks such as crane hook blocks standing under load. Fit practice for NU240-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 240, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 240 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 58 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 880/1060 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU240-ECML?", "a": "SKF NU 240 ECML is a single-row caged cylindrical roller bearing with 200 mm bore, 360 mm OD and 58 mm width per ISO 15. SKF lists C 880 kN, C0 1060 kN, Pu 106 kN, reference speed 1,900 r/min and limiting speed 3,200 r/min, mass about 26500 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU240-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU240-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU240", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×360×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ240-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×360×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU240-ECML", "SKF NU 240 ECML" ], "locale_variants": {} }, { "sku": "NU244-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 244 ECML", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 400, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 1290, "fatigue_load_limit_kN": 125, "max_rpm": 3000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3000, "weight_g": 37000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 244 ECML resolves to a 220×400×65 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1060 kN and C0 1290 kN, size the bearing on the 220×400 mm ISO 15 envelope and check the 125 kN Pu against the equivalent-load floor; the catalogue lists 1,700 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. Fit practice for NU244-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 244, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 244 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1060/1290 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU244-ECML?", "a": "SKF NU 244 ECML is a single-row caged cylindrical roller bearing with 220 mm bore, 400 mm OD and 65 mm width per ISO 15. SKF lists C 1060 kN, C0 1290 kN, Pu 125 kN, reference speed 1,700 r/min and limiting speed 3,000 r/min, mass about 37000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU244-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU244-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU244", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×400×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ244-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×65 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP244-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×65 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU244-ECML", "SKF NU 244 ECML" ], "locale_variants": {} }, { "sku": "NU248-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 248 MA", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 440, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 952, "static_load_kN": 1370, "fatigue_load_limit_kN": 129, "max_rpm": 2200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "weight_g": 51500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 248 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 240×440×72 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 51500 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 1.44 (1370 against 952 kN), and the Pu figure 129 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 240 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 248, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 248 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 72 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 952/1370 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU248-MA?", "a": "SKF NU 248 MA is a single-row caged cylindrical roller bearing with 240 mm bore, 440 mm OD and 72 mm width per ISO 15. SKF lists C 952 kN, C0 1370 kN, Pu 129 kN, reference speed 1,600 r/min and limiting speed 2,200 r/min, mass about 51500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU248-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU248-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU248", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ248-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×440×72 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP248-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×440×72 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU248-MA", "SKF NU 248 MA" ], "locale_variants": {} }, { "sku": "NU252-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 252 MA", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 480, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1170, "static_load_kN": 1700, "fatigue_load_limit_kN": 150, "max_rpm": 2000, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "weight_g": 68500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 252 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 260×480×80 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 68500 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1170 kN and C0 1700 kN, size the bearing on the 260×480 mm ISO 15 envelope and check the 150 kN Pu against the equivalent-load floor; the catalogue lists 1,400 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 260 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 252, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 252 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 1170/1700 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU252-MA?", "a": "SKF NU 252 MA is a single-row caged cylindrical roller bearing with 260 mm bore, 480 mm OD and 80 mm width per ISO 15. SKF lists C 1170 kN, C0 1700 kN, Pu 150 kN, reference speed 1,400 r/min and limiting speed 2,000 r/min, mass about 68500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU252-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU252-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU252", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ252-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×480×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP252-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×480×80 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU252-MA", "SKF NU 252 MA" ], "locale_variants": {} }, { "sku": "NU256-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 256 MA", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 500, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1190, "static_load_kN": 1800, "fatigue_load_limit_kN": 156, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 71500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 256 MA is a single-row caged cylindrical roller bearing sized 280×500×80 mm — a dimension series 2 (light-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 110.0 mm and the catalogue mass 71500 g; at 1190 kN dynamic rating this is roughly 4.25 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 256, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 256 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 1190/1800 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU256-MA?", "a": "SKF NU 256 MA is a single-row caged cylindrical roller bearing with 280 mm bore, 500 mm OD and 80 mm width per ISO 15. SKF lists C 1190 kN, C0 1800 kN, Pu 156 kN, reference speed 1,400 r/min and limiting speed 1,900 r/min, mass about 71500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU256-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU256-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU256", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ256-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 280×500×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU256-MA", "SKF NU 256 MA" ], "locale_variants": {} }, { "sku": "NU260-M", "brand": "SKF", "manufacturer_designation": "SKF NU 260 M", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 540, "B_mm": 85, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1420, "static_load_kN": 2120, "fatigue_load_limit_kN": 183, "max_rpm": 1400, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1400, "weight_g": 89500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU260-M is the 300 mm bore entry in the NU200 range: a 300×540×85 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1420 kN / C0 2120 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU260-M: the catalogue lists 1,300 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. The mass entry 89500 g covers the complete catalogue execution. Fit practice for NU260-M: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 260, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 260 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1420/2120 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU260-M?", "a": "SKF NU 260 M is a single-row caged cylindrical roller bearing with 300 mm bore, 540 mm OD and 85 mm width per ISO 15. SKF lists C 1420 kN, C0 2120 kN, Pu 183 kN, reference speed 1,300 r/min and limiting speed 1,400 r/min, mass about 89500 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU260-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU260-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU260", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NU260", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU260-M", "SKF NU 260 M" ], "locale_variants": {} }, { "sku": "NU264-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 264 ECM", "series": "NU200-series", "type": "cylindrical_roller", "d_mm": 320, "D_mm": 580, "B_mm": 92, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1830, "static_load_kN": 2750, "fatigue_load_limit_kN": 232, "max_rpm": 1200, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1200, "weight_g": 115000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU264-ECM is the 320 mm bore entry in the NU200 range: a 320×580×92 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1830 kN / C0 2750 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1830 kN and C0 2750 kN, size the bearing on the 320×580 mm ISO 15 envelope and check the 232 kN Pu against the equivalent-load floor; the catalogue lists 1,000 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 264, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 264 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 580 mm raceway.", "The 1830/2750 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU264-ECM?", "a": "SKF NU 264 ECM is a single-row caged cylindrical roller bearing with 320 mm bore, 580 mm OD and 92 mm width per ISO 15. SKF lists C 1830 kN, C0 2750 kN, Pu 232 kN, reference speed 1,000 r/min and limiting speed 1,200 r/min, mass about 115000 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU264-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU264-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU264", "equiv_brand": "NTN", "level": "partial", "note": "Same 320×580×92 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU264", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU264-ECM", "SKF NU 264 ECM" ], "locale_variants": {} }, { "sku": "NU28-850-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 28/850 MA", "series": "NU2800-series", "type": "cylindrical_roller", "d_mm": 850, "D_mm": 1030, "B_mm": 106, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2120, "static_load_kN": 6000, "fatigue_load_limit_kN": 240, "max_rpm": 670, "reference_speed_rpm": 500, "limiting_speed_rpm": 670, "weight_g": 193000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 28/850 MA is a single-row caged cylindrical roller bearing sized 850×1030×106 mm — a dimension series 28 (slim section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Load-per-bore for the 850 mm seat is about 2.49 kN/mm, typical of dimension series 28 (slim section, wide); use C0 6000 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 28 (slim section, wide) envelope is shared with the N/NU/NJ/NUP executions of 28/850, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 28/850 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 106 mm-wide ring and concentrates load.", "The 2120/6000 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU28-850-MA?", "a": "SKF NU 28/850 MA is a single-row caged cylindrical roller bearing with 850 mm bore, 1030 mm OD and 106 mm width per ISO 15. SKF lists C 2120 kN, C0 6000 kN, Pu 240 kN, reference speed 500 r/min and limiting speed 670 r/min, mass about 193000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU28-850-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU28-850-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU28", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU28-850-MA", "SKF NU 28/850 MA" ], "locale_variants": {} }, { "sku": "NU29-500-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 29/500 ECMA", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 670, "B_mm": 100, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2050, "static_load_kN": 4250, "fatigue_load_limit_kN": 355, "max_rpm": 1200, "reference_speed_rpm": 900, "limiting_speed_rpm": 1200, "weight_g": 107000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 29/500 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 500×670×100 mm envelope, dimension series 29 (compact OD, normal width), with catalogue mass 107000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 2050 kN and C0 4250 kN, size the bearing on the 500×670 mm ISO 15 envelope and check the 355 kN Pu against the equivalent-load floor; the catalogue lists 900 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Fit practice for NU29-500-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 29/500 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 100 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2050/4250 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU29-500-ECMA?", "a": "SKF NU 29/500 ECMA is a single-row caged cylindrical roller bearing with 500 mm bore, 670 mm OD and 100 mm width per ISO 15. SKF lists C 2050 kN, C0 4250 kN, Pu 355 kN, reference speed 900 r/min and limiting speed 1,200 r/min, mass about 107000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU29-500-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU29-500-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU29", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU29-500-ECMA", "SKF NU 29/500 ECMA" ], "locale_variants": {} }, { "sku": "NU29-560-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 29/560 ECMA", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 560, "D_mm": 750, "B_mm": 112, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2460, "static_load_kN": 5700, "fatigue_load_limit_kN": 450, "max_rpm": 1000, "reference_speed_rpm": 800, "limiting_speed_rpm": 1000, "weight_g": 145000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU29-560-ECMA is the 560 mm bore entry in the NU2900 range: a 560×750×112 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 2460 kN / C0 5700 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 2460 kN and C0 5700 kN, size the bearing on the 560×750 mm ISO 15 envelope and check the 450 kN Pu against the equivalent-load floor; the catalogue lists 800 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 560 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/560, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 29/560 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 112 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 112 mm-wide ring and concentrates load.", "The 2460/5700 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU29-560-ECMA?", "a": "SKF NU 29/560 ECMA is a single-row caged cylindrical roller bearing with 560 mm bore, 750 mm OD and 112 mm width per ISO 15. SKF lists C 2460 kN, C0 5700 kN, Pu 450 kN, reference speed 800 r/min and limiting speed 1,000 r/min, mass about 145000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU29-560-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU29-560-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU29", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU29-560-ECMA", "SKF NU 29/560 ECMA" ], "locale_variants": {} }, { "sku": "NU29-630-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 29/630 ECMA/HB1", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 630, "D_mm": 850, "B_mm": 128, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3300, "static_load_kN": 7200, "fatigue_load_limit_kN": 510, "max_rpm": 900, "reference_speed_rpm": 700, "limiting_speed_rpm": 900, "weight_g": 224000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 630 mm shaft, SKF lists NU29-630-ECMA-HB1 as single-row caged cylindrical roller: 850 mm OD, 128 mm wide, Pu 510 kN, the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 3300 kN and C0 7200 kN, size the bearing on the 630×850 mm ISO 15 envelope and check the 510 kN Pu against the equivalent-load floor; the catalogue lists 700 r/min thermal reference speed and 900 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 630 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/630, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 29/630 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 128 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 128 mm-wide ring and concentrates load.", "The 3300/7200 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU29-630-ECMA-HB1?", "a": "SKF NU 29/630 ECMA/HB1 is a single-row caged cylindrical roller bearing with 630 mm bore, 850 mm OD and 128 mm width per ISO 15. SKF lists C 3300 kN, C0 7200 kN, Pu 510 kN, reference speed 700 r/min and limiting speed 900 r/min, mass about 224000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU29-630-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU29-630-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ29-630-ECMA-HB1", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 630×850×128 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU29-630-ECMA-HB1", "SKF NU 29/630 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU29-710-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 29/710 ECMA", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 710, "D_mm": 950, "B_mm": 140, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3740, "static_load_kN": 8300, "fatigue_load_limit_kN": 570, "max_rpm": 800, "reference_speed_rpm": 600, "limiting_speed_rpm": 800, "weight_g": 297000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 29/710 ECMA is a single-row caged cylindrical roller bearing sized 710×950×140 mm — a dimension series 29 (compact OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 710 mm seat is about 5.27 kN/mm, typical of dimension series 29 (compact OD, normal width); use C0 8300 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 710 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/710, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 29/710 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 950 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 140 mm-wide ring and concentrates load.", "The 3740/8300 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU29-710-ECMA?", "a": "SKF NU 29/710 ECMA is a single-row caged cylindrical roller bearing with 710 mm bore, 950 mm OD and 140 mm width per ISO 15. SKF lists C 3740 kN, C0 8300 kN, Pu 570 kN, reference speed 600 r/min and limiting speed 800 r/min, mass about 297000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU29-710-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU29-710-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU29", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU29-710-ECMA", "SKF NU 29/710 ECMA" ], "locale_variants": {} }, { "sku": "NU29-900-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 29/900 ECMA/HB1", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 900, "D_mm": 1180, "B_mm": 165, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5280, "static_load_kN": 12500, "fatigue_load_limit_kN": 800, "max_rpm": 560, "reference_speed_rpm": 430, "limiting_speed_rpm": 560, "weight_g": 514000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 29/900 ECMA/HB1 is a single-row caged cylindrical roller bearing sized 900×1180×165 mm — a dimension series 29 (compact OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 900 mm seat is about 5.87 kN/mm, typical of dimension series 29 (compact OD, normal width); use C0 12500 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/900, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 29/900 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5280/12500 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU29-900-ECMA-HB1?", "a": "SKF NU 29/900 ECMA/HB1 is a single-row caged cylindrical roller bearing with 900 mm bore, 1180 mm OD and 165 mm width per ISO 15. SKF lists C 5280 kN, C0 12500 kN, Pu 800 kN, reference speed 430 r/min and limiting speed 560 r/min, mass about 514000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU29-900-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU29-900-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU29", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU29-900-ECMA-HB1", "SKF NU 29/900 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU2984-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 2984 ECMA", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 420, "D_mm": 560, "B_mm": 82, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1400, "static_load_kN": 2850, "fatigue_load_limit_kN": 255, "max_rpm": 1500, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1500, "weight_g": 60000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 2984 ECMA resolves to a 420×560×82 mm single-row caged cylindrical roller bearing (dimension series 29 (compact OD, normal width)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NU2984-ECMA: the catalogue lists 1,100 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. The mass entry 60000 g covers the complete catalogue execution. Fit practice for NU2984-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 2984, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2984 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 560 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 82 mm-wide ring and concentrates load.", "The 1400/2850 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2984-ECMA?", "a": "SKF NU 2984 ECMA is a single-row caged cylindrical roller bearing with 420 mm bore, 560 mm OD and 82 mm width per ISO 15. SKF lists C 1400 kN, C0 2850 kN, Pu 255 kN, reference speed 1,100 r/min and limiting speed 1,500 r/min, mass about 60000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2984-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2984-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU2984", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2984-ECMA", "SKF NU 2984 ECMA" ], "locale_variants": {} }, { "sku": "NU2988-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 2988 ECML", "series": "NU2900-series", "type": "cylindrical_roller", "d_mm": 440, "D_mm": 600, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1870, "static_load_kN": 3900, "fatigue_load_limit_kN": 340, "max_rpm": 1600, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1600, "weight_g": 81000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 2988 ECML is a single-row caged cylindrical roller bearing sized 440×600×95 mm — a dimension series 29 (compact OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1870 kN and C0 3900 kN, size the bearing on the 440×600 mm ISO 15 envelope and check the 340 kN Pu against the equivalent-load floor; the catalogue lists 1,100 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Fit practice for NU2988-ECML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 2988, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 2988 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 95 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 600 mm raceway.", "The 1870/3900 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU2988-ECML?", "a": "SKF NU 2988 ECML is a single-row caged cylindrical roller bearing with 440 mm bore, 600 mm OD and 95 mm width per ISO 15. SKF lists C 1870 kN, C0 3900 kN, Pu 340 kN, reference speed 1,100 r/min and limiting speed 1,600 r/min, mass about 81000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU2988-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU2988-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2988-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 440×600×95 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU2988-ECML", "SKF NU 2988 ECML" ], "locale_variants": {} }, { "sku": "NU30-500-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 30/500 ECMA", "series": "NU3000-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 720, "B_mm": 167, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3800, "static_load_kN": 7350, "fatigue_load_limit_kN": 560, "max_rpm": 1100, "reference_speed_rpm": 750, "limiting_speed_rpm": 1100, "weight_g": 233000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU30-500-ECMA is the 500 mm bore entry in the NU3000 range: a 500×720×167 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 3800 kN / C0 7350 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 500 mm seat is about 7.60 kN/mm, typical of dimension series 30 (compact OD, normal width); use C0 7350 kN for static checks such as crane hook blocks standing under load. Fit practice for NU30-500-ECMA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 30 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 30/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 30/500 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 720 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 167 mm-wide ring and concentrates load.", "The 3800/7350 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU30-500-ECMA?", "a": "SKF NU 30/500 ECMA is a single-row caged cylindrical roller bearing with 500 mm bore, 720 mm OD and 167 mm width per ISO 15. SKF lists C 3800 kN, C0 7350 kN, Pu 560 kN, reference speed 750 r/min and limiting speed 1,100 r/min, mass about 233000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU30-500-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU30-500-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU30", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU30-500-ECMA", "SKF NU 30/500 ECMA" ], "locale_variants": {} }, { "sku": "NU303-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 303 ECP", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 17, "D_mm": 47, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 28.5, "static_load_kN": 20.4, "fatigue_load_limit_kN": 2.55, "max_rpm": 20000, "reference_speed_rpm": 17000, "limiting_speed_rpm": 20000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU303-ECP is the 17 mm bore entry in the NU300 range: a 17×47×14 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 28.5 kN / C0 20.4 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 28.5 kN and C0 20.4 kN, size the bearing on the 17×47 mm ISO 15 envelope and check the 2.55 kN Pu against the equivalent-load floor; the catalogue lists 17,000 r/min thermal reference speed and 20,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 303, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 303 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 14 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 14 mm-wide ring and concentrates load.", "The 28.5/20.4 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU303-ECP?", "a": "SKF NU 303 ECP is a single-row caged cylindrical roller bearing with 17 mm bore, 47 mm OD and 14 mm width per ISO 15. SKF lists C 28.5 kN, C0 20.4 kN, Pu 2.55 kN, reference speed 17,000 r/min and limiting speed 20,000 r/min, mass about 120 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU303-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU303-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N303-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×47×14 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ303-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×47×14 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU303-ECP", "SKF NU 303 ECP" ], "locale_variants": {} }, { "sku": "NU3068-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 3068 MA", "series": "NU3000-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 520, "B_mm": 133, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2200, "static_load_kN": 4150, "fatigue_load_limit_kN": 365, "max_rpm": 1700, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1700, "weight_g": 109000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 3068 MA denotes a single-row caged cylindrical roller bearing on the ISO 15 340×520×133 mm envelope, dimension series 30 (compact OD, normal width), with catalogue mass 109000 g. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 340 mm seat is about 6.47 kN/mm, typical of dimension series 30 (compact OD, normal width); use C0 4150 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 30 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 3068, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3068 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 520 mm raceway.", "The 2200/4150 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3068-MA?", "a": "SKF NU 3068 MA is a single-row caged cylindrical roller bearing with 340 mm bore, 520 mm OD and 133 mm width per ISO 15. SKF lists C 2200 kN, C0 4150 kN, Pu 365 kN, reference speed 1,100 r/min and limiting speed 1,700 r/min, mass about 109000 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3068-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3068-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3068", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3068-MA", "SKF NU 3068 MA" ], "locale_variants": {} }, { "sku": "NU3076-ECMP", "brand": "SKF", "manufacturer_designation": "SKF NU 3076 ECMP", "series": "NU3000-series", "type": "cylindrical_roller", "d_mm": 380, "D_mm": 560, "B_mm": 135, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2380, "static_load_kN": 4750, "fatigue_load_limit_kN": 400, "max_rpm": 1800, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1800, "weight_g": 109000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 3076 ECMP is a single-row caged cylindrical roller bearing sized 380×560×135 mm — a dimension series 30 (compact OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMP: the E-design ECMP execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. The radial section height is 90.0 mm and the catalogue mass 109000 g; at 2380 kN dynamic rating this is roughly 6.26 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 380 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 30 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 3076, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3076 ECMP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 135 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2380/4750 kN ratings are SKF catalogue 17000 (2018) values for the ECMP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3076-ECMP?", "a": "SKF NU 3076 ECMP is a single-row caged cylindrical roller bearing with 380 mm bore, 560 mm OD and 135 mm width per ISO 15. SKF lists C 2380 kN, C0 4750 kN, Pu 400 kN, reference speed 1,000 r/min and limiting speed 1,800 r/min, mass about 109000 g." }, { "q": "What does the NU designation and ECMP suffix mean?", "a": "The ECMP suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3076-ECMP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3076-ECMP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3076", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3076-ECMP", "SKF NU 3076 ECMP" ], "locale_variants": {} }, { "sku": "NU31-500-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 31/500 ECMA/HB1", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 500, "D_mm": 830, "B_mm": 264, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 6440, "static_load_kN": 12000, "fatigue_load_limit_kN": 880, "max_rpm": 1000, "reference_speed_rpm": 600, "limiting_speed_rpm": 1000, "weight_g": 595000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 31/500 ECMA/HB1 is a single-row caged cylindrical roller bearing sized 500×830×264 mm — a dimension series 31 (compact OD, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.86 (12000 against 6440 kN), and the Pu figure 880 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 600 r/min thermal reference speed and 1,000 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 31/500, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 31/500 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 264 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 830 mm raceway.", "The 6440/12000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU31-500-ECMA-HB1?", "a": "SKF NU 31/500 ECMA/HB1 is a single-row caged cylindrical roller bearing with 500 mm bore, 830 mm OD and 264 mm width per ISO 15. SKF lists C 6440 kN, C0 12000 kN, Pu 880 kN, reference speed 600 r/min and limiting speed 1,000 r/min, mass about 595000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU31-500-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU31-500-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU31", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU31-500-ECMA-HB1", "SKF NU 31/500 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU31-530-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 31/530 ECMA/HB1", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 530, "D_mm": 870, "B_mm": 272, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 7480, "static_load_kN": 14600, "fatigue_load_limit_kN": 1040, "max_rpm": 950, "reference_speed_rpm": 560, "limiting_speed_rpm": 950, "weight_g": 660000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 31/530 ECMA/HB1 denotes a single-row caged cylindrical roller bearing on the ISO 15 530×870×272 mm envelope, dimension series 31 (compact OD, wide), with catalogue mass 660000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. Selection arithmetic: C0/C ≈ 1.95 (14600 against 7480 kN), and the Pu figure 1040 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 560 r/min thermal reference speed and 950 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 31/530, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 31/530 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 870 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 272 mm-wide ring and concentrates load.", "The 7480/14600 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU31-530-ECMA-HB1?", "a": "SKF NU 31/530 ECMA/HB1 is a single-row caged cylindrical roller bearing with 530 mm bore, 870 mm OD and 272 mm width per ISO 15. SKF lists C 7480 kN, C0 14600 kN, Pu 1040 kN, reference speed 560 r/min and limiting speed 950 r/min, mass about 660000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU31-530-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU31-530-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU31", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU31-530-ECMA-HB1", "SKF NU 31/530 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU3156-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 3156 ECMA", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 280, "D_mm": 460, "B_mm": 146, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2290, "static_load_kN": 3900, "fatigue_load_limit_kN": 335, "max_rpm": 2000, "reference_speed_rpm": 1200, "limiting_speed_rpm": 2000, "weight_g": 101000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 3156 ECMA denotes a single-row caged cylindrical roller bearing on the ISO 15 280×460×146 mm envelope, dimension series 31 (compact OD, wide), with catalogue mass 101000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. With C 2290 kN and C0 3900 kN, size the bearing on the 280×460 mm ISO 15 envelope and check the 335 kN Pu against the equivalent-load floor; the catalogue lists 1,200 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 280 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3156, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3156 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "The 2290/3900 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3156-ECMA?", "a": "SKF NU 3156 ECMA is a single-row caged cylindrical roller bearing with 280 mm bore, 460 mm OD and 146 mm width per ISO 15. SKF lists C 2290 kN, C0 3900 kN, Pu 335 kN, reference speed 1,200 r/min and limiting speed 2,000 r/min, mass about 101000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3156-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3156-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3156", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3156-ECMA", "SKF NU 3156 ECMA" ], "locale_variants": {} }, { "sku": "NU3168-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 3168 ECMA", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 340, "D_mm": 580, "B_mm": 190, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3470, "static_load_kN": 5850, "fatigue_load_limit_kN": 490, "max_rpm": 1600, "reference_speed_rpm": 950, "limiting_speed_rpm": 1600, "weight_g": 217000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 3168 ECMA resolves to a 340×580×190 mm single-row caged cylindrical roller bearing (dimension series 31 (compact OD, wide)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.69 (5850 against 3470 kN), and the Pu figure 490 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 950 r/min thermal reference speed and 1,600 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3168, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3168 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 190 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 3470/5850 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3168-ECMA?", "a": "SKF NU 3168 ECMA is a single-row caged cylindrical roller bearing with 340 mm bore, 580 mm OD and 190 mm width per ISO 15. SKF lists C 3470 kN, C0 5850 kN, Pu 490 kN, reference speed 950 r/min and limiting speed 1,600 r/min, mass about 217000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3168-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3168-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3168", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3168-ECMA", "SKF NU 3168 ECMA" ], "locale_variants": {} }, { "sku": "NU3172-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 3172 ECMA", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 360, "D_mm": 600, "B_mm": 192, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3410, "static_load_kN": 6100, "fatigue_load_limit_kN": 490, "max_rpm": 1500, "reference_speed_rpm": 900, "limiting_speed_rpm": 1500, "weight_g": 226000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 360 mm shaft, SKF lists NU3172-ECMA as single-row caged cylindrical roller: 600 mm OD, 192 mm wide, Pu 490 kN, the catalogue lists 900 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NU3172-ECMA: the catalogue lists 900 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. The mass entry 226000 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3172, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3172 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 3410/6100 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3172-ECMA?", "a": "SKF NU 3172 ECMA is a single-row caged cylindrical roller bearing with 360 mm bore, 600 mm OD and 192 mm width per ISO 15. SKF lists C 3410 kN, C0 6100 kN, Pu 490 kN, reference speed 900 r/min and limiting speed 1,500 r/min, mass about 226000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3172-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3172-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3172", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3172-ECMA", "SKF NU 3172 ECMA" ], "locale_variants": {} }, { "sku": "NU3184-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 3184 ECMA", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 420, "D_mm": 700, "B_mm": 224, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 4950, "static_load_kN": 9000, "fatigue_load_limit_kN": 695, "max_rpm": 1300, "reference_speed_rpm": 750, "limiting_speed_rpm": 1300, "weight_g": 365000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 420 mm shaft, SKF lists NU3184-ECMA as single-row caged cylindrical roller: 700 mm OD, 224 mm wide, Pu 695 kN, the catalogue lists 750 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 140.0 mm and the catalogue mass 365000 g; at 4950 kN dynamic rating this is roughly 11.79 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 420 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3184, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3184 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 700 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 224 mm-wide ring and concentrates load.", "The 4950/9000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3184-ECMA?", "a": "SKF NU 3184 ECMA is a single-row caged cylindrical roller bearing with 420 mm bore, 700 mm OD and 224 mm width per ISO 15. SKF lists C 4950 kN, C0 9000 kN, Pu 695 kN, reference speed 750 r/min and limiting speed 1,300 r/min, mass about 365000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3184-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3184-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3184", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3184-ECMA", "SKF NU 3184 ECMA" ], "locale_variants": {} }, { "sku": "NU3188-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 3188 ECMA/HB1", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 440, "D_mm": 720, "B_mm": 226, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5120, "static_load_kN": 10000, "fatigue_load_limit_kN": 765, "max_rpm": 1200, "reference_speed_rpm": 700, "limiting_speed_rpm": 1200, "weight_g": 388000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 3188 ECMA/HB1 denotes a single-row caged cylindrical roller bearing on the ISO 15 440×720×226 mm envelope, dimension series 31 (compact OD, wide), with catalogue mass 388000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Selection arithmetic: C0/C ≈ 1.95 (10000 against 5120 kN), and the Pu figure 765 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 700 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3188, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3188 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 226 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5120/10000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3188-ECMA-HB1?", "a": "SKF NU 3188 ECMA/HB1 is a single-row caged cylindrical roller bearing with 440 mm bore, 720 mm OD and 226 mm width per ISO 15. SKF lists C 5120 kN, C0 10000 kN, Pu 765 kN, reference speed 700 r/min and limiting speed 1,200 r/min, mass about 388000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3188-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3188-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3188", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3188-ECMA-HB1", "SKF NU 3188 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU3192-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 3192 ECMA/HB1", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 460, "D_mm": 760, "B_mm": 240, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5280, "static_load_kN": 9650, "fatigue_load_limit_kN": 735, "max_rpm": 1100, "reference_speed_rpm": 670, "limiting_speed_rpm": 1100, "weight_g": 450000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU3192-ECMA-HB1 is the 460 mm bore entry in the NU3100 range: a 460×760×240 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 5280 kN / C0 9650 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 150.0 mm and the catalogue mass 450000 g; at 5280 kN dynamic rating this is roughly 11.48 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 460 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3192, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3192 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 760 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 240 mm-wide ring and concentrates load.", "The 5280/9650 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3192-ECMA-HB1?", "a": "SKF NU 3192 ECMA/HB1 is a single-row caged cylindrical roller bearing with 460 mm bore, 760 mm OD and 240 mm width per ISO 15. SKF lists C 5280 kN, C0 9650 kN, Pu 735 kN, reference speed 670 r/min and limiting speed 1,100 r/min, mass about 450000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3192-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3192-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3192", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3192-ECMA-HB1", "SKF NU 3192 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU3196-ECMA-HB1", "brand": "SKF", "manufacturer_designation": "SKF NU 3196 ECMA/HB1", "series": "NU3100-series", "type": "cylindrical_roller", "d_mm": 480, "D_mm": 790, "B_mm": 248, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 5940, "static_load_kN": 10800, "fatigue_load_limit_kN": 800, "max_rpm": 1100, "reference_speed_rpm": 630, "limiting_speed_rpm": 1100, "weight_g": 507000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU3196-ECMA-HB1 is the 480 mm bore entry in the NU3100 range: a 480×790×248 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 5940 kN / C0 10800 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA/HB1: the basic execution supplied with a standard pressed-steel cage. With C 5940 kN and C0 10800 kN, size the bearing on the 480×790 mm ISO 15 envelope and check the 800 kN Pu against the equivalent-load floor; the catalogue lists 630 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 480 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 31 (compact OD, wide) envelope is shared with the N/NU/NJ/NUP executions of 3196, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3196 ECMA/HB1 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 790 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 5940/10800 kN ratings are SKF catalogue 17000 (2018) values for the ECMA/HB1 execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3196-ECMA-HB1?", "a": "SKF NU 3196 ECMA/HB1 is a single-row caged cylindrical roller bearing with 480 mm bore, 790 mm OD and 248 mm width per ISO 15. SKF lists C 5940 kN, C0 10800 kN, Pu 800 kN, reference speed 630 r/min and limiting speed 1,100 r/min, mass about 507000 g." }, { "q": "What does the NU designation and ECMA/HB1 suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3196-ECMA-HB1 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3196-ECMA-HB1 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3196", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3196-ECMA-HB1", "SKF NU 3196 ECMA/HB1" ], "locale_variants": {} }, { "sku": "NU321-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 321 ECP", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 105, "D_mm": 225, "B_mm": 49, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 500, "static_load_kN": 500, "fatigue_load_limit_kN": 57, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 8500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 105 mm shaft, SKF lists NU321-ECP as single-row caged cylindrical roller: 225 mm OD, 49 mm wide, Pu 57 kN, the catalogue lists 3,200 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 500 kN and C0 500 kN, size the bearing on the 105×225 mm ISO 15 envelope and check the 57 kN Pu against the equivalent-load floor; the catalogue lists 3,200 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 321, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 321 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 225 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 49 mm-wide ring and concentrates load.", "The 500/500 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU321-ECP?", "a": "SKF NU 321 ECP is a single-row caged cylindrical roller bearing with 105 mm bore, 225 mm OD and 49 mm width per ISO 15. SKF lists C 500 kN, C0 500 kN, Pu 57 kN, reference speed 3,200 r/min and limiting speed 3,800 r/min, mass about 8500 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU321-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU321-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU321", "equiv_brand": "NTN", "level": "partial", "note": "Same 105×225×49 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N321-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×225×49 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ321-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×225×49 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU321-ECP", "SKF NU 321 ECP" ], "locale_variants": {} }, { "sku": "NU322-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 322 ECP", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 240, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 530, "static_load_kN": 540, "fatigue_load_limit_kN": 61, "max_rpm": 3400, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3400, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 322 ECP is a single-row caged cylindrical roller bearing sized 110×240×50 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NU322-ECP: the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 10500 g covers the complete catalogue execution. Fit practice for NU322-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 322, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 322 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.", "The 530/540 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU322-ECP?", "a": "SKF NU 322 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 530 kN, C0 540 kN, Pu 61 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 10500 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU322-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU322-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU322", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×240×50 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ322-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU322-ECP", "SKF NU 322 ECP" ], "locale_variants": {} }, { "sku": "NU324-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 324 ECP", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 260, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 610, "static_load_kN": 620, "fatigue_load_limit_kN": 69.5, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 324 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 120×260×55 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 13000 g. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.02 (620 against 610 kN), and the Pu figure 69.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Fit practice for NU324-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 324, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 324 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 55 mm-wide ring and concentrates load.", "The 610/620 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU324-ECP?", "a": "SKF NU 324 ECP is a single-row caged cylindrical roller bearing with 120 mm bore, 260 mm OD and 55 mm width per ISO 15. SKF lists C 610 kN, C0 620 kN, Pu 69.5 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 13000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU324-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU324-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU324", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×260×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N324-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ324-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP324-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU324-ECP", "SKF NU 324 ECP" ], "locale_variants": {} }, { "sku": "NU326-ECP", "brand": "SKF", "manufacturer_designation": "SKF NU 326 ECP", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 280, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 720, "static_load_kN": 750, "fatigue_load_limit_kN": 81.5, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 16000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 326 ECP resolves to a 130×280×58 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NU326-ECP: the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 16000 g covers the complete catalogue execution. Fit practice for NU326-ECP: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 326, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 326 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 58 mm-wide ring and concentrates load.", "The 720/750 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU326-ECP?", "a": "SKF NU 326 ECP is a single-row caged cylindrical roller bearing with 130 mm bore, 280 mm OD and 58 mm width per ISO 15. SKF lists C 720 kN, C0 750 kN, Pu 81.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 16000 g." }, { "q": "What does the NU designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU326-ECP take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU326-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU326", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×280×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N326-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ326-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP326-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU326-ECP", "SKF NU 326 ECP" ], "locale_variants": {} }, { "sku": "NU328-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 328 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 300, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 780, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 140 mm shaft, SKF lists NU328-ECM as single-row caged cylindrical roller: 300 mm OD, 62 mm wide, Pu 88 kN, the catalogue lists 2,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.06 (830 against 780 kN), and the Pu figure 88 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Fit practice for NU328-ECM: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 328, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 328 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 62 mm-wide ring and concentrates load.", "The 780/830 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU328-ECM?", "a": "SKF NU 328 ECM is a single-row caged cylindrical roller bearing with 140 mm bore, 300 mm OD and 62 mm width per ISO 15. SKF lists C 780 kN, C0 830 kN, Pu 88 kN, reference speed 2,400 r/min and limiting speed 2,800 r/min, mass about 22500 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU328-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU328-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU328", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×300×62 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ328-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUP328-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NUP execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU328-ECM", "SKF NU 328 ECM" ], "locale_variants": {} }, { "sku": "NU330-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 330 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 320, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 900, "static_load_kN": 965, "fatigue_load_limit_kN": 100, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 26500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU330-ECM is the 150 mm bore entry in the NU300 range: a 150×320×65 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 900 kN / C0 965 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 85.0 mm and the catalogue mass 26500 g; at 900 kN dynamic rating this is roughly 6.00 kN of C per millimetre of bore before application factors. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 150 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 330, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 330 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "The 900/965 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU330-ECM?", "a": "SKF NU 330 ECM is a single-row caged cylindrical roller bearing with 150 mm bore, 320 mm OD and 65 mm width per ISO 15. SKF lists C 900 kN, C0 965 kN, Pu 100 kN, reference speed 2,200 r/min and limiting speed 2,600 r/min, mass about 26500 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU330-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU330-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU330", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×320×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ330-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×320×65 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU330-ECM", "SKF NU 330 ECM" ], "locale_variants": {} }, { "sku": "NU332-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 332 ECML", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 340, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1000, "static_load_kN": 1080, "fatigue_load_limit_kN": 112, "max_rpm": 3600, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3600, "weight_g": 31000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 160 mm shaft, SKF lists NU332-ECML as single-row caged cylindrical roller: 340 mm OD, 68 mm wide, Pu 112 kN, the catalogue lists 2,000 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Speed planning for NU332-ECML: the catalogue lists 2,000 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. The mass entry 31000 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 332, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 332 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 68 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1000/1080 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU332-ECML?", "a": "SKF NU 332 ECML is a single-row caged cylindrical roller bearing with 160 mm bore, 340 mm OD and 68 mm width per ISO 15. SKF lists C 1000 kN, C0 1080 kN, Pu 112 kN, reference speed 2,000 r/min and limiting speed 3,600 r/min, mass about 31000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU332-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU332-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU332", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×340×68 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ332-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×340×68 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU332-ECML", "SKF NU 332 ECML" ], "locale_variants": {} }, { "sku": "NU334-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 334 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 360, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 952, "static_load_kN": 1180, "fatigue_load_limit_kN": 116, "max_rpm": 2200, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2200, "weight_g": 33000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 334 ECM denotes a single-row caged cylindrical roller bearing on the ISO 15 170×360×72 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 33000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. The radial section height is 95.0 mm and the catalogue mass 33000 g; at 952 kN dynamic rating this is roughly 5.60 kN of C per millimetre of bore before application factors. Fit practice for NU334-ECM: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 334, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 334 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 72 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "The 952/1180 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU334-ECM?", "a": "SKF NU 334 ECM is a single-row caged cylindrical roller bearing with 170 mm bore, 360 mm OD and 72 mm width per ISO 15. SKF lists C 952 kN, C0 1180 kN, Pu 116 kN, reference speed 1,700 r/min and limiting speed 2,200 r/min, mass about 33000 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU334-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU334-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU334", "equiv_brand": "NTN", "level": "partial", "note": "Same 170×360×72 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU334", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU334-ECM", "SKF NU 334 ECM" ], "locale_variants": {} }, { "sku": "NU336-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 336 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 380, "B_mm": 75, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1020, "static_load_kN": 1290, "fatigue_load_limit_kN": 125, "max_rpm": 2200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "weight_g": 42500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 336 ECM resolves to a 180×380×75 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Speed planning for NU336-ECM: the catalogue lists 1,600 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. The mass entry 42500 g covers the complete catalogue execution. Fit practice for NU336-ECM: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 336, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 336 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "The 1020/1290 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU336-ECM?", "a": "SKF NU 336 ECM is a single-row caged cylindrical roller bearing with 180 mm bore, 380 mm OD and 75 mm width per ISO 15. SKF lists C 1020 kN, C0 1290 kN, Pu 125 kN, reference speed 1,600 r/min and limiting speed 2,200 r/min, mass about 42500 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU336-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU336-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU336", "equiv_brand": "NTN", "level": "partial", "note": "Same 180×380×75 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ336-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×380×75 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU336-ECM", "SKF NU 336 ECM" ], "locale_variants": {} }, { "sku": "NU338-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 338 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 400, "B_mm": 78, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1140, "static_load_kN": 1500, "fatigue_load_limit_kN": 143, "max_rpm": 2000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "weight_g": 50000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU338-ECM is the 190 mm bore entry in the NU300 range: a 190×400×78 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1140 kN / C0 1500 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.32 (1500 against 1140 kN), and the Pu figure 143 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,500 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Fit practice for NU338-ECM: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 338, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 338 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1140/1500 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU338-ECM?", "a": "SKF NU 338 ECM is a single-row caged cylindrical roller bearing with 190 mm bore, 400 mm OD and 78 mm width per ISO 15. SKF lists C 1140 kN, C0 1500 kN, Pu 143 kN, reference speed 1,500 r/min and limiting speed 2,000 r/min, mass about 50000 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU338-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU338-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU338", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×400×78 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU338", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU338-ECM", "SKF NU 338 ECM" ], "locale_variants": {} }, { "sku": "NU340-ECML", "brand": "SKF", "manufacturer_designation": "SKF NU 340 ECML", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 420, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1230, "static_load_kN": 1630, "fatigue_load_limit_kN": 150, "max_rpm": 2800, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2800, "weight_g": 57000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 340 ECML is a single-row caged cylindrical roller bearing sized 200×420×80 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU340-ECML: the catalogue lists 1,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. The mass entry 57000 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 340, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 340 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "The 1230/1630 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU340-ECML?", "a": "SKF NU 340 ECML is a single-row caged cylindrical roller bearing with 200 mm bore, 420 mm OD and 80 mm width per ISO 15. SKF lists C 1230 kN, C0 1630 kN, Pu 150 kN, reference speed 1,400 r/min and limiting speed 2,800 r/min, mass about 57000 g." }, { "q": "What does the NU designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU340-ECML take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU340-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU340", "equiv_brand": "NTN", "level": "partial", "note": "Same 200×420×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ340-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×420×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU340-ECML", "SKF NU 340 ECML" ], "locale_variants": {} }, { "sku": "NU344-M", "brand": "SKF", "manufacturer_designation": "SKF NU 344 M", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 460, "B_mm": 88, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1210, "static_load_kN": 1630, "fatigue_load_limit_kN": 150, "max_rpm": 1700, "reference_speed_rpm": 1500, "limiting_speed_rpm": 1700, "weight_g": 75000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 220 mm shaft, SKF lists NU344-M as single-row caged cylindrical roller: 460 mm OD, 88 mm wide, Pu 150 kN, the catalogue lists 1,500 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix M: the basic (non-E) M execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 120.0 mm and the catalogue mass 75000 g; at 1210 kN dynamic rating this is roughly 5.50 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 344, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 344 M and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 88 mm-wide ring and concentrates load.", "The 1210/1630 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU344-M?", "a": "SKF NU 344 M is a single-row caged cylindrical roller bearing with 220 mm bore, 460 mm OD and 88 mm width per ISO 15. SKF lists C 1210 kN, C0 1630 kN, Pu 150 kN, reference speed 1,500 r/min and limiting speed 1,700 r/min, mass about 75000 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU344-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU344-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU344", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ344-M", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×460×88 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU344-M", "SKF NU 344 M" ], "locale_variants": {} }, { "sku": "NU348-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 348 MA", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 500, "B_mm": 95, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1450, "static_load_kN": 2000, "fatigue_load_limit_kN": 180, "max_rpm": 2000, "reference_speed_rpm": 1300, "limiting_speed_rpm": 2000, "weight_g": 94500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 348 MA is a single-row caged cylindrical roller bearing sized 240×500×95 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 130.0 mm and the catalogue mass 94500 g; at 1450 kN dynamic rating this is roughly 6.04 kN of C per millimetre of bore before application factors. Fit practice for NU348-MA: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 348, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 348 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 95 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "The 1450/2000 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU348-MA?", "a": "SKF NU 348 MA is a single-row caged cylindrical roller bearing with 240 mm bore, 500 mm OD and 95 mm width per ISO 15. SKF lists C 1450 kN, C0 2000 kN, Pu 180 kN, reference speed 1,300 r/min and limiting speed 2,000 r/min, mass about 94500 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU348-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU348-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU348", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ348-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×500×95 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU348-MA", "SKF NU 348 MA" ], "locale_variants": {} }, { "sku": "NU352-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 352 ECMA", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 540, "B_mm": 102, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1940, "static_load_kN": 2700, "fatigue_load_limit_kN": 236, "max_rpm": 1800, "reference_speed_rpm": 1100, "limiting_speed_rpm": 1800, "weight_g": 121000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU352-ECMA is the 260 mm bore entry in the NU300 range: a 260×540×102 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1940 kN / C0 2700 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1940 kN and C0 2700 kN, size the bearing on the 260×540 mm ISO 15 envelope and check the 236 kN Pu against the equivalent-load floor; the catalogue lists 1,100 r/min thermal reference speed and 1,800 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 260 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 352, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 352 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1940/2700 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU352-ECMA?", "a": "SKF NU 352 ECMA is a single-row caged cylindrical roller bearing with 260 mm bore, 540 mm OD and 102 mm width per ISO 15. SKF lists C 1940 kN, C0 2700 kN, Pu 236 kN, reference speed 1,100 r/min and limiting speed 1,800 r/min, mass about 121000 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU352-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU352-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU352", "equiv_brand": "NTN", "level": "partial", "note": "Same 260×540×102 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NU352", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU352-ECMA", "SKF NU 352 ECMA" ], "locale_variants": {} }, { "sku": "NU360-ECM", "brand": "SKF", "manufacturer_designation": "SKF NU 360 ECM", "series": "NU300-series", "type": "cylindrical_roller", "d_mm": 300, "D_mm": 620, "B_mm": 109, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2330, "static_load_kN": 3350, "fatigue_load_limit_kN": 280, "max_rpm": 1200, "reference_speed_rpm": 950, "limiting_speed_rpm": 1200, "weight_g": 174000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 300 mm shaft, SKF lists NU360-ECM as single-row caged cylindrical roller: 620 mm OD, 109 mm wide, Pu 280 kN, the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.44 (3350 against 2330 kN), and the Pu figure 280 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 950 r/min thermal reference speed and 1,200 r/min mechanical limiting speed. Fit practice for NU360-ECM: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 360, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 360 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 109 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 109 mm-wide ring and concentrates load.", "The 2330/3350 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU360-ECM?", "a": "SKF NU 360 ECM is a single-row caged cylindrical roller bearing with 300 mm bore, 620 mm OD and 109 mm width per ISO 15. SKF lists C 2330 kN, C0 3350 kN, Pu 280 kN, reference speed 950 r/min and limiting speed 1,200 r/min, mass about 174000 g." }, { "q": "What does the NU designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU360-ECM take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU360-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU360", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU360-ECM", "SKF NU 360 ECM" ], "locale_variants": {} }, { "sku": "NU3980-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NU 3980 ECMA", "series": "NU3900-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 540, "B_mm": 106, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1760, "static_load_kN": 3750, "fatigue_load_limit_kN": 320, "max_rpm": 1500, "reference_speed_rpm": 1000, "limiting_speed_rpm": 1500, "weight_g": 74500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU3980-ECMA is the 400 mm bore entry in the NU3900 range: a 400×540×106 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1760 kN / C0 3750 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NU3980-ECMA: the catalogue lists 1,000 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. The mass entry 74500 g covers the complete catalogue execution. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 400 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 39 (compact OD) envelope is shared with the N/NU/NJ/NUP executions of 3980, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 3980 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 540 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 106 mm-wide ring and concentrates load.", "The 1760/3750 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU3980-ECMA?", "a": "SKF NU 3980 ECMA is a single-row caged cylindrical roller bearing with 400 mm bore, 540 mm OD and 106 mm width per ISO 15. SKF lists C 1760 kN, C0 3750 kN, Pu 320 kN, reference speed 1,000 r/min and limiting speed 1,500 r/min, mass about 74500 g." }, { "q": "What does the NU designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU3980-ECMA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU3980-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU3980", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU3980-ECMA", "SKF NU 3980 ECMA" ], "locale_variants": {} }, { "sku": "NU406-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 406 MA", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 60.5, "static_load_kN": 53, "fatigue_load_limit_kN": 6.8, "max_rpm": 11000, "reference_speed_rpm": 9000, "limiting_speed_rpm": 11000, "weight_g": 750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 30 mm shaft, SKF lists NU406-MA as single-row caged cylindrical roller: 90 mm OD, 23 mm wide, Pu 6.8 kN, the catalogue lists 9,000 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 60.5 kN and C0 53 kN, size the bearing on the 30×90 mm ISO 15 envelope and check the 6.8 kN Pu against the equivalent-load floor; the catalogue lists 9,000 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 30 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 406, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 406 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 23 mm-wide ring and concentrates load.", "The 60.5/53 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU406-MA?", "a": "SKF NU 406 MA is a single-row caged cylindrical roller bearing with 30 mm bore, 90 mm OD and 23 mm width per ISO 15. SKF lists C 60.5 kN, C0 53 kN, Pu 6.8 kN, reference speed 9,000 r/min and limiting speed 11,000 r/min, mass about 750 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU406-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU406-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU406", "equiv_brand": "NTN", "level": "partial", "note": "Same 30×90×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ406-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×90×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU406-MA", "SKF NU 406 MA" ], "locale_variants": {} }, { "sku": "NU407", "brand": "SKF", "manufacturer_designation": "SKF NU 407", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 100, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 76.5, "static_load_kN": 69.5, "fatigue_load_limit_kN": 9, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 1000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU407 is the 35 mm bore entry in the NU400 range: a 35×100×25 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 76.5 kN / C0 69.5 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. With C 76.5 kN and C0 69.5 kN, size the bearing on the 35×100 mm ISO 15 envelope and check the 9 kN Pu against the equivalent-load floor; the catalogue lists 8,000 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 407, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 407 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 76.5/69.5 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU407?", "a": "SKF NU 407 is a single-row caged cylindrical roller bearing with 35 mm bore, 100 mm OD and 25 mm width per ISO 15. SKF lists C 76.5 kN, C0 69.5 kN, Pu 9 kN, reference speed 8,000 r/min and limiting speed 9,500 r/min, mass about 1000 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU407 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU407 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU407-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ407", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×100×25 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU407", "SKF NU 407" ], "locale_variants": {} }, { "sku": "NU408-M", "brand": "SKF", "manufacturer_designation": "SKF NU 408 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 96.8, "static_load_kN": 90, "fatigue_load_limit_kN": 11.6, "max_rpm": 8500, "reference_speed_rpm": 7000, "limiting_speed_rpm": 8500, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU408-M is the 40 mm bore entry in the NU400 range: a 40×110×27 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 96.8 kN / C0 90 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix M: the basic (non-E) M execution with a machined brass cage, standard for the larger and earlier-design sizes. Selection arithmetic: C0/C ≈ 0.93 (90 against 96.8 kN), and the Pu figure 11.6 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 7,000 r/min thermal reference speed and 8,500 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 40 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 408, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 408 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 96.8/90 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU408-M?", "a": "SKF NU 408 M is a single-row caged cylindrical roller bearing with 40 mm bore, 110 mm OD and 27 mm width per ISO 15. SKF lists C 96.8 kN, C0 90 kN, Pu 11.6 kN, reference speed 7,000 r/min and limiting speed 8,500 r/min, mass about 1300 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU408-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU408-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU408", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ408-M", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×110×27 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU408-M", "SKF NU 408 M" ], "locale_variants": {} }, { "sku": "NU409", "brand": "SKF", "manufacturer_designation": "SKF NU 409", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 120, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 106, "static_load_kN": 102, "fatigue_load_limit_kN": 13.4, "max_rpm": 7500, "reference_speed_rpm": 6700, "limiting_speed_rpm": 7500, "weight_g": 1650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 45 mm shaft, SKF lists NU409 as single-row caged cylindrical roller: 120 mm OD, 29 mm wide, Pu 13.4 kN, the catalogue lists 6,700 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. With C 106 kN and C0 102 kN, size the bearing on the 45×120 mm ISO 15 envelope and check the 13.4 kN Pu against the equivalent-load floor; the catalogue lists 6,700 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Fit practice for NU409: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 409, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 409 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 29 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 29 mm-wide ring and concentrates load.", "The 106/102 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU409?", "a": "SKF NU 409 is a single-row caged cylindrical roller bearing with 45 mm bore, 120 mm OD and 29 mm width per ISO 15. SKF lists C 106 kN, C0 102 kN, Pu 13.4 kN, reference speed 6,700 r/min and limiting speed 7,500 r/min, mass about 1650 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU409 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU409 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU409-NTN", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×120×29 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ409", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×120×29 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU409", "SKF NU 409" ], "locale_variants": {} }, { "sku": "NU410", "brand": "SKF", "manufacturer_designation": "SKF NU 410", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 130, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 130, "static_load_kN": 127, "fatigue_load_limit_kN": 16.6, "max_rpm": 7000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7000, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 410 is a single-row caged cylindrical roller bearing sized 50×130×31 mm — a dimension series 4 (heavy-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 50 mm seat is about 2.60 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 127 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 410, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 410 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 130/127 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU410?", "a": "SKF NU 410 is a single-row caged cylindrical roller bearing with 50 mm bore, 130 mm OD and 31 mm width per ISO 15. SKF lists C 130 kN, C0 127 kN, Pu 16.6 kN, reference speed 6,000 r/min and limiting speed 7,000 r/min, mass about 2000 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU410 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU410 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU410-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ410", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×130×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU410", "SKF NU 410" ], "locale_variants": {} }, { "sku": "NU411", "brand": "SKF", "manufacturer_designation": "SKF NU 411", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 142, "static_load_kN": 140, "fatigue_load_limit_kN": 18.6, "max_rpm": 6300, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6300, "weight_g": 2500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU411 is the 55 mm bore entry in the NU400 range: a 55×140×33 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 142 kN / C0 140 kN. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 55 mm seat is about 2.58 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 140 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 55 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 411, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 411 and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "The 142/140 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU411?", "a": "SKF NU 411 is a single-row caged cylindrical roller bearing with 55 mm bore, 140 mm OD and 33 mm width per ISO 15. SKF lists C 142 kN, C0 140 kN, Pu 18.6 kN, reference speed 5,600 r/min and limiting speed 6,300 r/min, mass about 2500 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU411 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU411 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU411-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ411", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×140×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU411", "SKF NU 411" ], "locale_variants": {} }, { "sku": "NU412", "brand": "SKF", "manufacturer_designation": "SKF NU 412", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 168, "static_load_kN": 173, "fatigue_load_limit_kN": 22, "max_rpm": 6000, "reference_speed_rpm": 5000, "limiting_speed_rpm": 6000, "weight_g": 3000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NU 412 denotes a single-row caged cylindrical roller bearing on the ISO 15 60×150×35 mm envelope, dimension series 4 (heavy-section ISO 15 envelope), with catalogue mass 3000 g. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 60 mm seat is about 2.80 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 173 kN for static checks such as crane hook blocks standing under load. Fit practice for NU412: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 412, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 412 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 35 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 35 mm-wide ring and concentrates load.", "The 168/173 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU412?", "a": "SKF NU 412 is a single-row caged cylindrical roller bearing with 60 mm bore, 150 mm OD and 35 mm width per ISO 15. SKF lists C 168 kN, C0 173 kN, Pu 22 kN, reference speed 5,000 r/min and limiting speed 6,000 r/min, mass about 3000 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU412 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU412 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU412-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ412", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×150×35 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU412", "SKF NU 412" ], "locale_variants": {} }, { "sku": "NU413", "brand": "SKF", "manufacturer_designation": "SKF NU 413", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 160, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 183, "static_load_kN": 190, "fatigue_load_limit_kN": 24, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 3550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 65 mm shaft, SKF lists NU413 as single-row caged cylindrical roller: 160 mm OD, 37 mm wide, Pu 24 kN, the catalogue lists 4,800 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 65 mm seat is about 2.82 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 190 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 413, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 413 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 183/190 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU413?", "a": "SKF NU 413 is a single-row caged cylindrical roller bearing with 65 mm bore, 160 mm OD and 37 mm width per ISO 15. SKF lists C 183 kN, C0 190 kN, Pu 24 kN, reference speed 4,800 r/min and limiting speed 5,600 r/min, mass about 3550 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU413 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU413 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU413-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ413", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×160×37 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU413", "SKF NU 413" ], "locale_variants": {} }, { "sku": "NU414-MA", "brand": "SKF", "manufacturer_designation": "SKF NU 414 MA", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 180, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 229, "static_load_kN": 240, "fatigue_load_limit_kN": 30, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 5250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU414-MA is the 70 mm bore entry in the NU400 range: a 70×180×42 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 229 kN / C0 240 kN. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. Load-per-bore for the 70 mm seat is about 3.27 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 240 kN for static checks such as crane hook blocks standing under load. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 414, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 414 MA and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 42 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 229/240 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU414-MA?", "a": "SKF NU 414 MA is a single-row caged cylindrical roller bearing with 70 mm bore, 180 mm OD and 42 mm width per ISO 15. SKF lists C 229 kN, C0 240 kN, Pu 30 kN, reference speed 4,300 r/min and limiting speed 5,000 r/min, mass about 5250 g." }, { "q": "What does the NU designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU414-MA take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU414-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU414", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ414-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×180×42 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU414-MA", "SKF NU 414 MA" ], "locale_variants": {} }, { "sku": "NU415", "brand": "SKF", "manufacturer_designation": "SKF NU 415", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 190, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 264, "static_load_kN": 280, "fatigue_load_limit_kN": 34, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800, "weight_g": 6200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 415 is a single-row caged cylindrical roller bearing sized 75×190×45 mm — a dimension series 4 (heavy-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NU prefix: two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. This makes the execution non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 75 mm seat is about 3.52 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 280 kN for static checks such as crane hook blocks standing under load. Fit practice for NU415: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 415, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 415 and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "The 264/280 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU415?", "a": "SKF NU 415 is a single-row caged cylindrical roller bearing with 75 mm bore, 190 mm OD and 45 mm width per ISO 15. SKF lists C 264 kN, C0 280 kN, Pu 34 kN, reference speed 4,000 r/min and limiting speed 4,800 r/min, mass about 6200 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU415 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU415 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU415-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ415", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×190×45 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU415", "SKF NU 415" ], "locale_variants": {} }, { "sku": "NU416", "brand": "SKF", "manufacturer_designation": "SKF NU 416", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 200, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 303, "static_load_kN": 320, "fatigue_load_limit_kN": 39, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 7250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU416 is the 80 mm bore entry in the NU400 range: a 80×200×48 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 303 kN / C0 320 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Load-per-bore for the 80 mm seat is about 3.79 kN/mm, typical of dimension series 4 (heavy-section ISO 15 envelope); use C0 320 kN for static checks such as crane hook blocks standing under load. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 416, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 416 and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 303/320 kN ratings are SKF catalogue 17000 (2018) values for the basic execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU416?", "a": "SKF NU 416 is a single-row caged cylindrical roller bearing with 80 mm bore, 200 mm OD and 48 mm width per ISO 15. SKF lists C 303 kN, C0 320 kN, Pu 39 kN, reference speed 3,800 r/min and limiting speed 4,500 r/min, mass about 7250 g." }, { "q": "What does the NU designation and plain suffix mean?", "a": "The plain designation (no cage suffix) identifies the basic execution supplied with a standard pressed-steel cage. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU416 take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU416 compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU416-NTN", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ416", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×200×48 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU416", "SKF NU 416" ], "locale_variants": {} }, { "sku": "NU418-M", "brand": "SKF", "manufacturer_designation": "SKF NU 418 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 225, "B_mm": 54, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 380, "static_load_kN": 415, "fatigue_load_limit_kN": 48, "max_rpm": 4000, "reference_speed_rpm": 3400, "limiting_speed_rpm": 4000, "weight_g": 10000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 90 mm shaft, SKF lists NU418-M as single-row caged cylindrical roller: 225 mm OD, 54 mm wide, Pu 48 kN, the catalogue lists 3,400 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NU418-M: the catalogue lists 3,400 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. The mass entry 10000 g covers the complete catalogue execution. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 418, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 418 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 380/415 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU418-M?", "a": "SKF NU 418 M is a single-row caged cylindrical roller bearing with 90 mm bore, 225 mm OD and 54 mm width per ISO 15. SKF lists C 380 kN, C0 415 kN, Pu 48 kN, reference speed 3,400 r/min and limiting speed 4,000 r/min, mass about 10000 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU418-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU418-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU418", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU418-M", "SKF NU 418 M" ], "locale_variants": {} }, { "sku": "NU419-M", "brand": "SKF", "manufacturer_designation": "SKF NU 419 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 240, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 413, "static_load_kN": 455, "fatigue_load_limit_kN": 52, "max_rpm": 3600, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3600, "weight_g": 13500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NU 419 M resolves to a 95×240×55 mm single-row caged cylindrical roller bearing (dimension series 4 (heavy-section ISO 15 envelope)); two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix M: the basic (non-E) M execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 72.5 mm and the catalogue mass 13500 g; at 413 kN dynamic rating this is roughly 4.35 kN of C per millimetre of bore before application factors. Assembly note: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Heat steel rings inductively to max 120 °C.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 419, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 419 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 55 mm-wide ring and concentrates load.", "The 413/455 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU419-M?", "a": "SKF NU 419 M is a single-row caged cylindrical roller bearing with 95 mm bore, 240 mm OD and 55 mm width per ISO 15. SKF lists C 413 kN, C0 455 kN, Pu 52 kN, reference speed 3,200 r/min and limiting speed 3,600 r/min, mass about 13500 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU419-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU419-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU419", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU419-M", "SKF NU 419 M" ], "locale_variants": {} }, { "sku": "NU420-M", "brand": "SKF", "manufacturer_designation": "SKF NU 420 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 250, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 457, "static_load_kN": 520, "fatigue_load_limit_kN": 58.5, "max_rpm": 3600, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3600, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NU 420 M is a single-row caged cylindrical roller bearing sized 100×250×58 mm — a dimension series 4 (heavy-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix M: the basic (non-E) M execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 75.0 mm and the catalogue mass 15500 g; at 457 kN dynamic rating this is roughly 4.57 kN of C per millimetre of bore before application factors. Fit practice for NU420-M: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 420, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 420 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 250 mm raceway.", "The 457/520 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU420-M?", "a": "SKF NU 420 M is a single-row caged cylindrical roller bearing with 100 mm bore, 250 mm OD and 58 mm width per ISO 15. SKF lists C 457 kN, C0 520 kN, Pu 58.5 kN, reference speed 3,000 r/min and limiting speed 3,600 r/min, mass about 15500 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU420-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU420-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU420", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU420-M", "SKF NU 420 M" ], "locale_variants": {} }, { "sku": "NU421-M", "brand": "SKF", "manufacturer_designation": "SKF NU 421 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 105, "D_mm": 260, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 501, "static_load_kN": 570, "fatigue_load_limit_kN": 64, "max_rpm": 3400, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3400, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 105 mm shaft, SKF lists NU421-M as single-row caged cylindrical roller: 260 mm OD, 60 mm wide, Pu 64 kN, the catalogue lists 2,800 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.14 (570 against 501 kN), and the Pu figure 64 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,800 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Mounting: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. A 105 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 421, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 421 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 60 mm-wide ring and concentrates load.", "The 501/570 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU421-M?", "a": "SKF NU 421 M is a single-row caged cylindrical roller bearing with 105 mm bore, 260 mm OD and 60 mm width per ISO 15. SKF lists C 501 kN, C0 570 kN, Pu 64 kN, reference speed 2,800 r/min and limiting speed 3,400 r/min, mass about 17500 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU421-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU421-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU421", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU421-M", "SKF NU 421 M" ], "locale_variants": {} }, { "sku": "NU424-M", "brand": "SKF", "manufacturer_designation": "SKF NU 424 M", "series": "NU400-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 310, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 644, "static_load_kN": 735, "fatigue_load_limit_kN": 78, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 27500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NU424-M is the 120 mm bore entry in the NU400 range: a 120×310×72 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 644 kN / C0 735 kN. Structurally, the NU design has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable. In arrangement terms it is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. Reading the order-string suffix M: the basic (non-E) M execution with a machined brass cage, standard for the larger and earlier-design sizes. Speed planning for NU424-M: the catalogue lists 2,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. The mass entry 27500 g covers the complete catalogue execution. Fit practice for NU424-M: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NU bearing where axial load must be carried — the design carries radial load only", "The dimension series 4 (heavy-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 424, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 424 M and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 310 mm raceway.", "The 644/735 kN ratings are SKF catalogue 17000 (2018) values for the M execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NU424-M?", "a": "SKF NU 424 M is a single-row caged cylindrical roller bearing with 120 mm bore, 310 mm OD and 72 mm width per ISO 15. SKF lists C 644 kN, C0 735 kN, Pu 78 kN, reference speed 2,400 r/min and limiting speed 2,800 r/min, mass about 27500 g." }, { "q": "What does the NU designation and M suffix mean?", "a": "The M suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable." }, { "q": "Can NU424-M take axial load and locate the shaft?", "a": "No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty." }, { "q": "How does NU424-M compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NU424", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NU424-M", "SKF NU 424 M" ], "locale_variants": {} }, { "sku": "NUH2220-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2220 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 180, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 400, "static_load_kN": 475, "fatigue_load_limit_kN": 57, "max_rpm": 4500, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4500, "weight_g": 5100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2220 ECMH resolves to a 100×180×46 mm high-capacity cylindrical roller bearing (dimension series 22 (light-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Speed planning for NUH2220-ECMH: the catalogue lists 4,000 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. The mass entry 5100 g covers the complete catalogue execution. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "wind-turbine rotor pinion shafts", "heavy mining and cement gear drives", "wind turbine gearbox planetary and intermediate shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2220 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 400/475 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2220-ECMH?", "a": "SKF NUH 2220 ECMH is a high-capacity cylindrical roller bearing with 100 mm bore, 180 mm OD and 46 mm width per ISO 15. SKF lists C 400 kN, C0 475 kN, Pu 57 kN, reference speed 4,000 r/min and limiting speed 4,500 r/min, mass about 5100 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2220-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2220-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2220", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2220-ECMH", "SKF NUH 2220 ECMH" ], "locale_variants": {} }, { "sku": "NUH2222-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2222 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 200, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 465, "static_load_kN": 550, "fatigue_load_limit_kN": 64, "max_rpm": 4000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4000, "weight_g": 7300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2222 ECMH is a high-capacity cylindrical roller bearing sized 110×200×53 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.18 (550 against 465 kN), and the Pu figure 64 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Fit practice for NUH2222-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "heavy mining and cement gear drives", "wind turbine gearbox planetary and intermediate shafts", "wind-turbine rotor pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2222 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 53 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 465/550 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2222-ECMH?", "a": "SKF NUH 2222 ECMH is a high-capacity cylindrical roller bearing with 110 mm bore, 200 mm OD and 53 mm width per ISO 15. SKF lists C 465 kN, C0 550 kN, Pu 64 kN, reference speed 3,600 r/min and limiting speed 4,000 r/min, mass about 7300 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2222-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2222-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2222", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2222-ECMH", "SKF NUH 2222 ECMH" ], "locale_variants": {} }, { "sku": "NUH2224-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2224 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 215, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 550, "static_load_kN": 670, "fatigue_load_limit_kN": 76.5, "max_rpm": 3600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3600, "weight_g": 9000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2224 ECMH resolves to a 120×215×58 mm high-capacity cylindrical roller bearing (dimension series 22 (light-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 550 kN and C0 670 kN, size the bearing on the 120×215 mm ISO 15 envelope and check the 76.5 kN Pu against the equivalent-load floor; the catalogue lists 3,400 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Fit practice for NUH2224-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2224 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 550/670 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2224-ECMH?", "a": "SKF NUH 2224 ECMH is a high-capacity cylindrical roller bearing with 120 mm bore, 215 mm OD and 58 mm width per ISO 15. SKF lists C 550 kN, C0 670 kN, Pu 76.5 kN, reference speed 3,400 r/min and limiting speed 3,600 r/min, mass about 9000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2224-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2224-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2224", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2224-ECMH", "SKF NUH 2224 ECMH" ], "locale_variants": {} }, { "sku": "NUH2226-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2226 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 230, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 630, "static_load_kN": 780, "fatigue_load_limit_kN": 88, "max_rpm": 3400, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3400, "weight_g": 11000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 130 mm shaft, SKF lists NUH2226-ECMH as high-capacity cylindrical roller: 230 mm OD, 64 mm wide, Pu 88 kN, the catalogue lists 3,200 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for NUH2226-ECMH: the catalogue lists 3,200 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 11000 g covers the complete catalogue execution. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2226 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 64 mm-wide ring and concentrates load.", "The 630/780 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2226-ECMH?", "a": "SKF NUH 2226 ECMH is a high-capacity cylindrical roller bearing with 130 mm bore, 230 mm OD and 64 mm width per ISO 15. SKF lists C 630 kN, C0 780 kN, Pu 88 kN, reference speed 3,200 r/min and limiting speed 3,400 r/min, mass about 11000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2226-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2226-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2226", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2226-ECMH", "SKF NUH 2226 ECMH" ], "locale_variants": {} }, { "sku": "NUH2228-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2228 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 250, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 680, "static_load_kN": 880, "fatigue_load_limit_kN": 96.5, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 14500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2228 ECMH resolves to a 140×250×68 mm high-capacity cylindrical roller bearing (dimension series 22 (light-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Selection arithmetic: C0/C ≈ 1.29 (880 against 680 kN), and the Pu figure 96.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Fit practice for NUH2228-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2228 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 68 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 68 mm-wide ring and concentrates load.", "The 680/880 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2228-ECMH?", "a": "SKF NUH 2228 ECMH is a high-capacity cylindrical roller bearing with 140 mm bore, 250 mm OD and 68 mm width per ISO 15. SKF lists C 680 kN, C0 880 kN, Pu 96.5 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 14500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2228-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2228-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2228-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2228-ECMH", "SKF NUH 2228 ECMH" ], "locale_variants": {} }, { "sku": "NUH2230-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2230 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 270, "B_mm": 73, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 780, "static_load_kN": 1040, "fatigue_load_limit_kN": 112, "max_rpm": 2800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 2800, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUH 2230 ECMH denotes a high-capacity cylindrical roller bearing on the ISO 15 150×270×73 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 18000 g. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.33 (1040 against 780 kN), and the Pu figure 112 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,600 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 150 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2230 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 270 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 73 mm-wide ring and concentrates load.", "The 780/1040 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2230-ECMH?", "a": "SKF NUH 2230 ECMH is a high-capacity cylindrical roller bearing with 150 mm bore, 270 mm OD and 73 mm width per ISO 15. SKF lists C 780 kN, C0 1040 kN, Pu 112 kN, reference speed 2,600 r/min and limiting speed 2,800 r/min, mass about 18000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2230-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2230-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2230-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×73 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2230-ECMH", "SKF NUH 2230 ECMH" ], "locale_variants": {} }, { "sku": "NUH2232-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2232 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 290, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 980, "static_load_kN": 1270, "fatigue_load_limit_kN": 134, "max_rpm": 2600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2600, "weight_g": 23000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2232-ECMH is the 160 mm bore entry in the NUH2200 range: a 160×290×80 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 980 kN / C0 1270 kN. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 980 kN and C0 1270 kN, size the bearing on the 160×290 mm ISO 15 envelope and check the 134 kN Pu against the equivalent-load floor; the catalogue lists 2,400 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2232 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 980/1270 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2232-ECMH?", "a": "SKF NUH 2232 ECMH is a high-capacity cylindrical roller bearing with 160 mm bore, 290 mm OD and 80 mm width per ISO 15. SKF lists C 980 kN, C0 1270 kN, Pu 134 kN, reference speed 2,400 r/min and limiting speed 2,600 r/min, mass about 23000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2232-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2232-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2232-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×80 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2232-ECMH", "SKF NUH 2232 ECMH" ], "locale_variants": {} }, { "sku": "NUH2234-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2234 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 310, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1600, "static_load_kN": 1530, "fatigue_load_limit_kN": 156, "max_rpm": 2400, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2400, "weight_g": 28500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUH 2234 ECMH denotes a high-capacity cylindrical roller bearing on the ISO 15 170×310×86 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 28500 g. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Speed planning for NUH2234-ECMH: the catalogue lists 2,200 r/min thermal reference speed and 2,400 r/min mechanical limiting speed. The mass entry 28500 g covers the complete catalogue execution. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 170 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2234 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1600/1530 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2234-ECMH?", "a": "SKF NUH 2234 ECMH is a high-capacity cylindrical roller bearing with 170 mm bore, 310 mm OD and 86 mm width per ISO 15. SKF lists C 1600 kN, C0 1530 kN, Pu 156 kN, reference speed 2,200 r/min and limiting speed 2,400 r/min, mass about 28500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2234-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2234-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2234-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 170×310×86 mm, but catalogue C/C0 ratings differ between executions (1600/1530 vs 1160/1530 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2234-ECMH", "SKF NUH 2234 ECMH" ], "locale_variants": {} }, { "sku": "NUH2236-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2236 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 320, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1200, "static_load_kN": 1600, "fatigue_load_limit_kN": 166, "max_rpm": 2400, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2400, "weight_g": 29500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2236-ECMH is the 180 mm bore entry in the NUH2200 range: a 180×320×86 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 1200 kN / C0 1600 kN. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.33 (1600 against 1200 kN), and the Pu figure 166 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,200 r/min thermal reference speed and 2,400 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 180 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2236 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1200/1600 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2236-ECMH?", "a": "SKF NUH 2236 ECMH is a high-capacity cylindrical roller bearing with 180 mm bore, 320 mm OD and 86 mm width per ISO 15. SKF lists C 1200 kN, C0 1600 kN, Pu 166 kN, reference speed 2,200 r/min and limiting speed 2,400 r/min, mass about 29500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2236-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2236-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2236-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×320×86 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2236-ECMH", "SKF NUH 2236 ECMH" ], "locale_variants": {} }, { "sku": "NUH2238-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2238 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 340, "B_mm": 92, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1320, "static_load_kN": 1760, "fatigue_load_limit_kN": 180, "max_rpm": 2200, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2200, "weight_g": 36000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2238 ECMH is a high-capacity cylindrical roller bearing sized 190×340×92 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 1320 kN and C0 1760 kN, size the bearing on the 190×340 mm ISO 15 envelope and check the 180 kN Pu against the equivalent-load floor; the catalogue lists 2,000 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2238 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 92 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1320/1760 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2238-ECMH?", "a": "SKF NUH 2238 ECMH is a high-capacity cylindrical roller bearing with 190 mm bore, 340 mm OD and 92 mm width per ISO 15. SKF lists C 1320 kN, C0 1760 kN, Pu 180 kN, reference speed 2,000 r/min and limiting speed 2,200 r/min, mass about 36000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2238-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2238-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2238-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×92 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2238-ECMH", "SKF NUH 2238 ECMH" ], "locale_variants": {} }, { "sku": "NUH2240-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2240 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 360, "B_mm": 98, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1460, "static_load_kN": 2000, "fatigue_load_limit_kN": 200, "max_rpm": 2200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2200, "weight_g": 43500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2240 ECMH is a high-capacity cylindrical roller bearing sized 200×360×98 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 1460 kN and C0 2000 kN, size the bearing on the 200×360 mm ISO 15 envelope and check the 200 kN Pu against the equivalent-load floor; the catalogue lists 1,900 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2240 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1460/2000 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2240-ECMH?", "a": "SKF NUH 2240 ECMH is a high-capacity cylindrical roller bearing with 200 mm bore, 360 mm OD and 98 mm width per ISO 15. SKF lists C 1460 kN, C0 2000 kN, Pu 200 kN, reference speed 1,900 r/min and limiting speed 2,200 r/min, mass about 43500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2240-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2240-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2240-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×360×98 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2240-ECMH", "SKF NUH 2240 ECMH" ], "locale_variants": {} }, { "sku": "NUH2244-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2244 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 400, "B_mm": 108, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1760, "static_load_kN": 2600, "fatigue_load_limit_kN": 240, "max_rpm": 1900, "reference_speed_rpm": 1600, "limiting_speed_rpm": 1900, "weight_g": 59000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 220 mm shaft, SKF lists NUH2244-ECMH as high-capacity cylindrical roller: 400 mm OD, 108 mm wide, Pu 240 kN, the catalogue lists 1,600 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.48 (2600 against 1760 kN), and the Pu figure 240 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2244 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1760/2600 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2244-ECMH?", "a": "SKF NUH 2244 ECMH is a high-capacity cylindrical roller bearing with 220 mm bore, 400 mm OD and 108 mm width per ISO 15. SKF lists C 1760 kN, C0 2600 kN, Pu 240 kN, reference speed 1,600 r/min and limiting speed 1,900 r/min, mass about 59000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2244-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2244-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2244-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×108 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2244-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×400×108 mm, but catalogue C/C0 ratings differ between executions (1760/2600 vs 2000/2600 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2244-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×400×108 mm, but catalogue C/C0 ratings differ between executions (1760/2600 vs 2000/2600 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2244-ECMH", "SKF NUH 2244 ECMH" ], "locale_variants": {} }, { "sku": "NUH2244-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2244 ECMH/PEX", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 400, "B_mm": 108, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2000, "static_load_kN": 2600, "fatigue_load_limit_kN": 240, "max_rpm": 1900, "reference_speed_rpm": 1700, "limiting_speed_rpm": 1900, "weight_g": 59000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2244-ECMH-PEX is the 220 mm bore entry in the NUH2200 range: a 220×400×108 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 2000 kN / C0 2600 kN. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Speed planning for NUH2244-ECMH-PEX: the catalogue lists 1,700 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. The mass entry 59000 g covers the complete catalogue execution. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 2000 kN / C0 2600 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2244-ECMH-PEX as a separate service part: do not substitute the standard NUH 2244 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2244 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 108 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 2000/2600 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2244-ECMH-PEX?", "a": "SKF NUH 2244 ECMH/PEX is a high-capacity cylindrical roller bearing with 220 mm bore, 400 mm OD and 108 mm width per ISO 15. SKF lists C 2000 kN, C0 2600 kN, Pu 240 kN, reference speed 1,700 r/min and limiting speed 1,900 r/min, mass about 59000 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2244-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2244-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2244-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×400×108 mm, but catalogue C/C0 ratings differ between executions (2000/2600 vs 1760/2600 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2244-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×108 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2244-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×400×108 mm, but catalogue C/C0 ratings differ between executions (2000/2600 vs 1760/2600 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2244-ECMH-PEX", "SKF NUH 2244 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2248-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2248 ECMH", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 440, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1980, "static_load_kN": 3050, "fatigue_load_limit_kN": 275, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 80000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 240 mm shaft, SKF lists NUH2248-ECMH as high-capacity cylindrical roller: 440 mm OD, 120 mm wide, Pu 275 kN, the catalogue lists 1,400 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Speed planning for NUH2248-ECMH: the catalogue lists 1,400 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. The mass entry 80000 g covers the complete catalogue execution. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2248 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 mm-wide ring and concentrates load.", "The 1980/3050 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2248-ECMH?", "a": "SKF NUH 2248 ECMH is a high-capacity cylindrical roller bearing with 240 mm bore, 440 mm OD and 120 mm width per ISO 15. SKF lists C 1980 kN, C0 3050 kN, Pu 275 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 80000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2248-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2248-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2248-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 240×440×120 mm, but catalogue C/C0 ratings differ between executions (1980/3050 vs 2279/3050 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2248-ECMH", "SKF NUH 2248 ECMH" ], "locale_variants": {} }, { "sku": "NUH2248-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2248 ECMH/PEX", "series": "NUH2200-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 440, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2279, "static_load_kN": 3050, "fatigue_load_limit_kN": 275, "max_rpm": 1700, "reference_speed_rpm": 1600, "limiting_speed_rpm": 1700, "weight_g": 80000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2248-ECMH-PEX is the 240 mm bore entry in the NUH2200 range: a 240×440×120 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 2279 kN / C0 3050 kN. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.34 (3050 against 2279 kN), and the Pu figure 275 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. Fit practice for NUH2248-ECMH-PEX: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 2279 kN / C0 3050 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2248-ECMH-PEX as a separate service part: do not substitute the standard NUH 2248 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2248 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 440 mm raceway.", "The 2279/3050 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2248-ECMH-PEX?", "a": "SKF NUH 2248 ECMH/PEX is a high-capacity cylindrical roller bearing with 240 mm bore, 440 mm OD and 120 mm width per ISO 15. SKF lists C 2279 kN, C0 3050 kN, Pu 275 kN, reference speed 1,600 r/min and limiting speed 1,700 r/min, mass about 80000 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2248-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2248-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2248-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 240×440×120 mm, but catalogue C/C0 ratings differ between executions (2279/3050 vs 1980/3050 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2248-ECMH-PEX", "SKF NUH 2248 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2320-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2320 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 215, "B_mm": 73, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 710, "static_load_kN": 800, "fatigue_load_limit_kN": 91.5, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 13000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2320 ECMH is a high-capacity cylindrical roller bearing sized 100×215×73 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 100 mm seat is about 7.10 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 800 kN for static checks such as crane hook blocks standing under load. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "wind-turbine rotor pinion shafts", "heavy mining and cement gear drives", "wind turbine gearbox planetary and intermediate shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2320 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 710/800 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2320-ECMH?", "a": "SKF NUH 2320 ECMH is a high-capacity cylindrical roller bearing with 100 mm bore, 215 mm OD and 73 mm width per ISO 15. SKF lists C 710 kN, C0 800 kN, Pu 91.5 kN, reference speed 3,200 r/min and limiting speed 3,800 r/min, mass about 13000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2320-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2320-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2320", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2320-ECMH", "SKF NUH 2320 ECMH" ], "locale_variants": {} }, { "sku": "NUH2322-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2322 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 240, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 830, "static_load_kN": 965, "fatigue_load_limit_kN": 110, "max_rpm": 3400, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3400, "weight_g": 18000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2322-ECMH is the 110 mm bore entry in the NUH2300 range: a 110×240×80 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 830 kN / C0 965 kN. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.16 (965 against 830 kN), and the Pu figure 110 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "wind-turbine rotor pinion shafts", "heavy mining and cement gear drives", "wind turbine gearbox planetary and intermediate shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2322 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 830/965 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2322-ECMH?", "a": "SKF NUH 2322 ECMH is a high-capacity cylindrical roller bearing with 110 mm bore, 240 mm OD and 80 mm width per ISO 15. SKF lists C 830 kN, C0 965 kN, Pu 110 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 18000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2322-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2322-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2322", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2322-ECMH", "SKF NUH 2322 ECMH" ], "locale_variants": {} }, { "sku": "NUH2324-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2324 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 260, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 965, "static_load_kN": 1120, "fatigue_load_limit_kN": 125, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2324 ECMH is a high-capacity cylindrical roller bearing sized 120×260×86 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 965 kN and C0 1120 kN, size the bearing on the 120×260 mm ISO 15 envelope and check the 125 kN Pu against the equivalent-load floor; the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2324 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 86 mm-wide ring and concentrates load.", "The 965/1120 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2324-ECMH?", "a": "SKF NUH 2324 ECMH is a high-capacity cylindrical roller bearing with 120 mm bore, 260 mm OD and 86 mm width per ISO 15. SKF lists C 965 kN, C0 1120 kN, Pu 125 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 22500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2324-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2324-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2324", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2324-ECMH", "SKF NUH 2324 ECMH" ], "locale_variants": {} }, { "sku": "NUH2326-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2326 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 280, "B_mm": 93, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1120, "static_load_kN": 1340, "fatigue_load_limit_kN": 146, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 28000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2326 ECMH resolves to a 130×280×93 mm high-capacity cylindrical roller bearing (dimension series 23 (medium-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Load-per-bore for the 130 mm seat is about 8.62 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 1340 kN for static checks such as crane hook blocks standing under load. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2326 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 93 mm-wide ring and concentrates load.", "The 1120/1340 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2326-ECMH?", "a": "SKF NUH 2326 ECMH is a high-capacity cylindrical roller bearing with 130 mm bore, 280 mm OD and 93 mm width per ISO 15. SKF lists C 1120 kN, C0 1340 kN, Pu 146 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 28000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2326-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2326-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2326-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×93 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2326-ECMH", "SKF NUH 2326 ECMH" ], "locale_variants": {} }, { "sku": "NUH2328-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2328 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 300, "B_mm": 102, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1250, "static_load_kN": 1530, "fatigue_load_limit_kN": 163, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 35000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2328 ECMH is a high-capacity cylindrical roller bearing sized 140×300×102 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Selection arithmetic: C0/C ≈ 1.22 (1530 against 1250 kN), and the Pu figure 163 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2328 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 102 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1250/1530 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2328-ECMH?", "a": "SKF NUH 2328 ECMH is a high-capacity cylindrical roller bearing with 140 mm bore, 300 mm OD and 102 mm width per ISO 15. SKF lists C 1250 kN, C0 1530 kN, Pu 163 kN, reference speed 2,400 r/min and limiting speed 2,800 r/min, mass about 35000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2328-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2328-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2328-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×102 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2328-ECMH", "SKF NUH 2328 ECMH" ], "locale_variants": {} }, { "sku": "NUH2330-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2330 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 320, "B_mm": 108, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1430, "static_load_kN": 1760, "fatigue_load_limit_kN": 183, "max_rpm": 2600, "reference_speed_rpm": 2200, "limiting_speed_rpm": 2600, "weight_g": 42000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 150 mm shaft, SKF lists NUH2330-ECMH as high-capacity cylindrical roller: 320 mm OD, 108 mm wide, Pu 183 kN, the catalogue lists 2,200 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.23 (1760 against 1430 kN), and the Pu figure 183 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,200 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Fit practice for NUH2330-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2330 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 320 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1430/1760 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2330-ECMH?", "a": "SKF NUH 2330 ECMH is a high-capacity cylindrical roller bearing with 150 mm bore, 320 mm OD and 108 mm width per ISO 15. SKF lists C 1430 kN, C0 1760 kN, Pu 183 kN, reference speed 2,200 r/min and limiting speed 2,600 r/min, mass about 42000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2330-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2330-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2330-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×320×108 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2330-ECMH", "SKF NUH 2330 ECMH" ], "locale_variants": {} }, { "sku": "NUH2332-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2332 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 340, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1400, "static_load_kN": 2000, "fatigue_load_limit_kN": 196, "max_rpm": 2400, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2400, "weight_g": 50500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUH 2332 ECMH denotes a high-capacity cylindrical roller bearing on the ISO 15 160×340×114 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 50500 g. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 1400 kN and C0 2000 kN, size the bearing on the 160×340 mm ISO 15 envelope and check the 196 kN Pu against the equivalent-load floor; the catalogue lists 1,800 r/min thermal reference speed and 2,400 r/min mechanical limiting speed. Fit practice for NUH2332-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2332 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 114 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1400/2000 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2332-ECMH?", "a": "SKF NUH 2332 ECMH is a high-capacity cylindrical roller bearing with 160 mm bore, 340 mm OD and 114 mm width per ISO 15. SKF lists C 1400 kN, C0 2000 kN, Pu 196 kN, reference speed 1,800 r/min and limiting speed 2,400 r/min, mass about 50500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2332-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2332-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2332-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×340×114 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2332-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 160×340×114 mm, but catalogue C/C0 ratings differ between executions (1400/2000 vs 1600/2000 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2332-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 160×340×114 mm, but catalogue C/C0 ratings differ between executions (1400/2000 vs 1600/2000 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2332-ECMH", "SKF NUH 2332 ECMH" ], "locale_variants": {} }, { "sku": "NUH2332-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2332 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 340, "B_mm": 114, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1600, "static_load_kN": 2000, "fatigue_load_limit_kN": 196, "max_rpm": 2400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 2400, "weight_g": 50500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2332 ECMH/PEX resolves to a 160×340×114 mm high-capacity cylindrical roller bearing (dimension series 23 (medium-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. With C 1600 kN and C0 2000 kN, size the bearing on the 160×340 mm ISO 15 envelope and check the 196 kN Pu against the equivalent-load floor; the catalogue lists 2,000 r/min thermal reference speed and 2,400 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 1600 kN / C0 2000 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2332-ECMH-PEX as a separate service part: do not substitute the standard NUH 2332 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2332 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 340 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 340 mm raceway.", "The 1600/2000 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2332-ECMH-PEX?", "a": "SKF NUH 2332 ECMH/PEX is a high-capacity cylindrical roller bearing with 160 mm bore, 340 mm OD and 114 mm width per ISO 15. SKF lists C 1600 kN, C0 2000 kN, Pu 196 kN, reference speed 2,000 r/min and limiting speed 2,400 r/min, mass about 50500 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2332-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2332-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2332-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 160×340×114 mm, but catalogue C/C0 ratings differ between executions (1600/2000 vs 1400/2000 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2332-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×340×114 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2332-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 160×340×114 mm, but catalogue C/C0 ratings differ between executions (1600/2000 vs 1400/2000 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2332-ECMH-PEX", "SKF NUH 2332 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2334-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2334 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 360, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1540, "static_load_kN": 2200, "fatigue_load_limit_kN": 216, "max_rpm": 2200, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2200, "weight_g": 59500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 170 mm shaft, SKF lists NUH2334-ECMH as high-capacity cylindrical roller: 360 mm OD, 120 mm wide, Pu 216 kN, the catalogue lists 1,700 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Load-per-bore for the 170 mm seat is about 9.06 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 2200 kN for static checks such as crane hook blocks standing under load. Assembly note: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2334 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1540/2200 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2334-ECMH?", "a": "SKF NUH 2334 ECMH is a high-capacity cylindrical roller bearing with 170 mm bore, 360 mm OD and 120 mm width per ISO 15. SKF lists C 1540 kN, C0 2200 kN, Pu 216 kN, reference speed 1,700 r/min and limiting speed 2,200 r/min, mass about 59500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2334-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2334-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2334-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×360×120 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2334-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1540/2200 vs 1760/2200 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2334-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1540/2200 vs 1760/2200 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2334-ECMH", "SKF NUH 2334 ECMH" ], "locale_variants": {} }, { "sku": "NUH2334-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2334 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 170, "D_mm": 360, "B_mm": 120, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1760, "static_load_kN": 2200, "fatigue_load_limit_kN": 216, "max_rpm": 2200, "reference_speed_rpm": 1900, "limiting_speed_rpm": 2200, "weight_g": 59500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2334 ECMH/PEX is a high-capacity cylindrical roller bearing sized 170×360×120 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Speed planning for NUH2334-ECMH-PEX: the catalogue lists 1,900 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. The mass entry 59500 g covers the complete catalogue execution. Fit practice for NUH2334-ECMH-PEX: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 1760 kN / C0 2200 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2334-ECMH-PEX as a separate service part: do not substitute the standard NUH 2334 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2334 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 360 mm raceway.", "The 1760/2200 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2334-ECMH-PEX?", "a": "SKF NUH 2334 ECMH/PEX is a high-capacity cylindrical roller bearing with 170 mm bore, 360 mm OD and 120 mm width per ISO 15. SKF lists C 1760 kN, C0 2200 kN, Pu 216 kN, reference speed 1,900 r/min and limiting speed 2,200 r/min, mass about 59500 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2334-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2334-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2334-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1760/2200 vs 1540/2200 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2334-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 170×360×120 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2334-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1760/2200 vs 1540/2200 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2334-ECMH-PEX", "SKF NUH 2334 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2336-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2336 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 380, "B_mm": 126, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1720, "static_load_kN": 2400, "fatigue_load_limit_kN": 232, "max_rpm": 2200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "weight_g": 68000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUH 2336 ECMH denotes a high-capacity cylindrical roller bearing on the ISO 15 180×380×126 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 68000 g. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.40 (2400 against 1720 kN), and the Pu figure 232 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 2,200 r/min mechanical limiting speed. Fit practice for NUH2336-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2336 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "The 1720/2400 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2336-ECMH?", "a": "SKF NUH 2336 ECMH is a high-capacity cylindrical roller bearing with 180 mm bore, 380 mm OD and 126 mm width per ISO 15. SKF lists C 1720 kN, C0 2400 kN, Pu 232 kN, reference speed 1,600 r/min and limiting speed 2,200 r/min, mass about 68000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2336-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2336-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2336-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×380×126 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2336-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 180×380×126 mm, but catalogue C/C0 ratings differ between executions (1720/2400 vs 1960/2400 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2336-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 180×380×126 mm, but catalogue C/C0 ratings differ between executions (1720/2400 vs 1960/2400 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2336-ECMH", "SKF NUH 2336 ECMH" ], "locale_variants": {} }, { "sku": "NUH2336-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2336 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 180, "D_mm": 380, "B_mm": 126, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1960, "static_load_kN": 2400, "fatigue_load_limit_kN": 232, "max_rpm": 2200, "reference_speed_rpm": 1800, "limiting_speed_rpm": 2200, "weight_g": 68000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2336 ECMH/PEX resolves to a 180×380×126 mm high-capacity cylindrical roller bearing (dimension series 23 (medium-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Load-per-bore for the 180 mm seat is about 10.89 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 2400 kN for static checks such as crane hook blocks standing under load. Fit practice for NUH2336-ECMH-PEX: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 1960 kN / C0 2400 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2336-ECMH-PEX as a separate service part: do not substitute the standard NUH 2336 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2336 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 380 mm raceway.", "The 1960/2400 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2336-ECMH-PEX?", "a": "SKF NUH 2336 ECMH/PEX is a high-capacity cylindrical roller bearing with 180 mm bore, 380 mm OD and 126 mm width per ISO 15. SKF lists C 1960 kN, C0 2400 kN, Pu 232 kN, reference speed 1,800 r/min and limiting speed 2,200 r/min, mass about 68000 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2336-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2336-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2336-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 180×380×126 mm, but catalogue C/C0 ratings differ between executions (1960/2400 vs 1720/2400 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2336-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 180×380×126 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2336-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 180×380×126 mm, but catalogue C/C0 ratings differ between executions (1960/2400 vs 1720/2400 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2336-ECMH-PEX", "SKF NUH 2336 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2338-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2338 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 400, "B_mm": 132, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1940, "static_load_kN": 2750, "fatigue_load_limit_kN": 255, "max_rpm": 2000, "reference_speed_rpm": 1500, "limiting_speed_rpm": 2000, "weight_g": 78500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2338-ECMH is the 190 mm bore entry in the NUH2300 range: a 190×400×132 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 1940 kN / C0 2750 kN. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 1940 kN and C0 2750 kN, size the bearing on the 190×400 mm ISO 15 envelope and check the 255 kN Pu against the equivalent-load floor; the catalogue lists 1,500 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Fit practice for NUH2338-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2338 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 132 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 1940/2750 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2338-ECMH?", "a": "SKF NUH 2338 ECMH is a high-capacity cylindrical roller bearing with 190 mm bore, 400 mm OD and 132 mm width per ISO 15. SKF lists C 1940 kN, C0 2750 kN, Pu 255 kN, reference speed 1,500 r/min and limiting speed 2,000 r/min, mass about 78500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2338-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2338-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2338-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×400×132 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2338-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 190×400×132 mm, but catalogue C/C0 ratings differ between executions (1940/2750 vs 2240/2750 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2338-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 190×400×132 mm, but catalogue C/C0 ratings differ between executions (1940/2750 vs 2240/2750 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2338-ECMH", "SKF NUH 2338 ECMH" ], "locale_variants": {} }, { "sku": "NUH2338-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2338 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 400, "B_mm": 132, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2240, "static_load_kN": 2750, "fatigue_load_limit_kN": 255, "max_rpm": 2000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 2000, "weight_g": 78500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 190 mm shaft, SKF lists NUH2338-ECMH-PEX as high-capacity cylindrical roller: 400 mm OD, 132 mm wide, Pu 255 kN, the catalogue lists 1,700 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.23 (2750 against 2240 kN), and the Pu figure 255 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,700 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. Fit practice for NUH2338-ECMH-PEX: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 2240 kN / C0 2750 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2338-ECMH-PEX as a separate service part: do not substitute the standard NUH 2338 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2338 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "The 2240/2750 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2338-ECMH-PEX?", "a": "SKF NUH 2338 ECMH/PEX is a high-capacity cylindrical roller bearing with 190 mm bore, 400 mm OD and 132 mm width per ISO 15. SKF lists C 2240 kN, C0 2750 kN, Pu 255 kN, reference speed 1,700 r/min and limiting speed 2,000 r/min, mass about 78500 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2338-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2338-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2338-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 190×400×132 mm, but catalogue C/C0 ratings differ between executions (2240/2750 vs 1940/2750 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2338-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×400×132 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2338-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 190×400×132 mm, but catalogue C/C0 ratings differ between executions (2240/2750 vs 1940/2750 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2338-ECMH-PEX", "SKF NUH 2338 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2340-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2340 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 420, "B_mm": 138, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2200, "static_load_kN": 3200, "fatigue_load_limit_kN": 300, "max_rpm": 1900, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1900, "weight_g": 92500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUH2340-ECMH is the 200 mm bore entry in the NUH2300 range: a 200×420×138 mm high-capacity cylindrical roller bearing with a one-piece machined brass cage, rated C 2200 kN / C0 3200 kN. The NUH configuration means a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring; functionally the bearing is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). With C 2200 kN and C0 3200 kN, size the bearing on the 200×420 mm ISO 15 envelope and check the 300 kN Pu against the equivalent-load floor; the catalogue lists 1,400 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Fit practice for NUH2340-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2340 using the /PEX loads.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 420 mm raceway.", "The 2200/3200 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2340-ECMH?", "a": "SKF NUH 2340 ECMH is a high-capacity cylindrical roller bearing with 200 mm bore, 420 mm OD and 138 mm width per ISO 15. SKF lists C 2200 kN, C0 3200 kN, Pu 300 kN, reference speed 1,400 r/min and limiting speed 1,900 r/min, mass about 92500 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2340-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2340-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2340-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×420×138 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NCF2340-ECJB-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 200×420×138 mm, but catalogue C/C0 ratings differ between executions (2200/3200 vs 2550/3200 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2340-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 200×420×138 mm, but catalogue C/C0 ratings differ between executions (2200/3200 vs 2550/3200 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2340-ECMH", "SKF NUH 2340 ECMH" ], "locale_variants": {} }, { "sku": "NUH2340-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2340 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 200, "D_mm": 420, "B_mm": 138, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2550, "static_load_kN": 3200, "fatigue_load_limit_kN": 300, "max_rpm": 1900, "reference_speed_rpm": 1600, "limiting_speed_rpm": 1900, "weight_g": 92500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2340 ECMH/PEX is a high-capacity cylindrical roller bearing sized 200×420×138 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Selection arithmetic: C0/C ≈ 1.25 (3200 against 2550 kN), and the Pu figure 300 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,600 r/min thermal reference speed and 1,900 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 200 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 2550 kN / C0 3200 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2340-ECMH-PEX as a separate service part: do not substitute the standard NUH 2340 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2340 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 2550/3200 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2340-ECMH-PEX?", "a": "SKF NUH 2340 ECMH/PEX is a high-capacity cylindrical roller bearing with 200 mm bore, 420 mm OD and 138 mm width per ISO 15. SKF lists C 2550 kN, C0 3200 kN, Pu 300 kN, reference speed 1,600 r/min and limiting speed 1,900 r/min, mass about 92500 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2340-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2340-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2340-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 200×420×138 mm, but catalogue C/C0 ratings differ between executions (2550/3200 vs 2200/3200 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NCF2340-ECJB-PEX", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 200×420×138 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2340-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 200×420×138 mm, but catalogue C/C0 ratings differ between executions (2550/3200 vs 2200/3200 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2340-ECMH-PEX", "SKF NUH 2340 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2344-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2344 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 460, "B_mm": 145, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2510, "static_load_kN": 3650, "fatigue_load_limit_kN": 335, "max_rpm": 1700, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1700, "weight_g": 116000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2344 ECMH resolves to a 220×460×145 mm high-capacity cylindrical roller bearing (dimension series 23 (medium-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.45 (3650 against 2510 kN), and the Pu figure 335 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 1,300 r/min thermal reference speed and 1,700 r/min mechanical limiting speed. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2344 using the /PEX loads.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 145 mm-wide ring and concentrates load.", "The 2510/3650 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2344-ECMH?", "a": "SKF NUH 2344 ECMH is a high-capacity cylindrical roller bearing with 220 mm bore, 460 mm OD and 145 mm width per ISO 15. SKF lists C 2510 kN, C0 3650 kN, Pu 335 kN, reference speed 1,300 r/min and limiting speed 1,700 r/min, mass about 116000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2344-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2344-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2344-ECJB", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×460×145 mm and equivalent catalogue ratings; the NCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NUH2344-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×460×145 mm, but catalogue C/C0 ratings differ between executions (2510/3650 vs 2900/3650 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2344-ECMH", "SKF NUH 2344 ECMH" ], "locale_variants": {} }, { "sku": "NUH2344-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2344 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 460, "B_mm": 145, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2900, "static_load_kN": 3650, "fatigue_load_limit_kN": 335, "max_rpm": 1700, "reference_speed_rpm": 1400, "limiting_speed_rpm": 1700, "weight_g": 116000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2344 ECMH/PEX is a high-capacity cylindrical roller bearing sized 220×460×145 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The radial section height is 120.0 mm and the catalogue mass 116000 g; at 2900 kN dynamic rating this is roughly 13.18 kN of C per millimetre of bore before application factors. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 2900 kN / C0 3650 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2344-ECMH-PEX as a separate service part: do not substitute the standard NUH 2344 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2344 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 460 mm raceway.", "The 2900/3650 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2344-ECMH-PEX?", "a": "SKF NUH 2344 ECMH/PEX is a high-capacity cylindrical roller bearing with 220 mm bore, 460 mm OD and 145 mm width per ISO 15. SKF lists C 2900 kN, C0 3650 kN, Pu 335 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 116000 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2344-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2344-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NCF2344-ECJB", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×460×145 mm, but catalogue C/C0 ratings differ between executions (2900/3650 vs 2510/3650 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent." }, { "equiv_sku": "NUH2344-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 220×460×145 mm, but catalogue C/C0 ratings differ between executions (2900/3650 vs 2510/3650 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2344-ECMH-PEX", "SKF NUH 2344 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUH2348-ECMH", "brand": "SKF", "manufacturer_designation": "SKF NUH 2348 ECMH", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 500, "B_mm": 155, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2750, "static_load_kN": 4000, "fatigue_load_limit_kN": 345, "max_rpm": 1500, "reference_speed_rpm": 1200, "limiting_speed_rpm": 1500, "weight_g": 143000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUH 2348 ECMH resolves to a 240×500×155 mm high-capacity cylindrical roller bearing (dimension series 23 (medium-section, wide)); a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. Reading the NUH prefix: a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. This makes the execution the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Load-per-bore for the 240 mm seat is about 11.46 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 4000 kN for static checks such as crane hook blocks standing under load. Fit practice for NUH2348-ECMH: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.", "applications": [ "offshore and marine heavy drive trains", "large mining mill pinion shafts", "multi-megawatt wind turbine main gearboxes" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NUH 2348 using the /PEX loads.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 155 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 155 mm-wide ring and concentrates load.", "The 2750/4000 kN ratings are SKF catalogue 17000 (2018) values for the ECMH execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2348-ECMH?", "a": "SKF NUH 2348 ECMH is a high-capacity cylindrical roller bearing with 240 mm bore, 500 mm OD and 155 mm width per ISO 15. SKF lists C 2750 kN, C0 4000 kN, Pu 345 kN, reference speed 1,200 r/min and limiting speed 1,500 r/min, mass about 143000 g." }, { "q": "What does the NUH designation and ECMH suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2348-ECMH take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2348-ECMH compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2348-ECMH-PEX", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 240×500×155 mm, but catalogue C/C0 ratings differ between executions (2750/4000 vs 3150/4000 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2348-ECMH", "SKF NUH 2348 ECMH" ], "locale_variants": {} }, { "sku": "NUH2348-ECMH-PEX", "brand": "SKF", "manufacturer_designation": "SKF NUH 2348 ECMH/PEX", "series": "NUH2300-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 500, "B_mm": 155, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 3150, "static_load_kN": 4000, "fatigue_load_limit_kN": 345, "max_rpm": 1500, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1500, "weight_g": 143000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUH 2348 ECMH/PEX is a high-capacity cylindrical roller bearing sized 240×500×155 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. Reading the order-string suffix ECMH/PEX: the high-capacity execution with a machined brass cage (the /PEX variant is the pinion-shaft special build). Speed planning for NUH2348-ECMH-PEX: the catalogue lists 1,300 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. The mass entry 143000 g covers the complete catalogue execution. Fit practice for NUH2348-ECMH-PEX: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 3150 kN / C0 4000 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2348-ECMH-PEX as a separate service part: do not substitute the standard NUH 2348 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.", "applications": [ "multi-megawatt wind turbine main gearboxes", "offshore and marine heavy drive trains", "large mining mill pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.", "The /PEX pinion build and the standard NUH 2348 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 500 mm raceway.", "The 3150/4000 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/PEX execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUH2348-ECMH-PEX?", "a": "SKF NUH 2348 ECMH/PEX is a high-capacity cylindrical roller bearing with 240 mm bore, 500 mm OD and 155 mm width per ISO 15. SKF lists C 3150 kN, C0 4000 kN, Pu 345 kN, reference speed 1,300 r/min and limiting speed 1,500 r/min, mass about 143000 g." }, { "q": "What does the NUH designation and ECMH/PEX suffix mean?", "a": "The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring." }, { "q": "Can NUH2348-ECMH-PEX take axial load and locate the shaft?", "a": "In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing." }, { "q": "How does NUH2348-ECMH-PEX compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUH2348-ECMH", "equiv_brand": "SKF", "level": "partial", "note": "Same ISO 15 envelope 240×500×155 mm, but catalogue C/C0 ratings differ between executions (3150/4000 vs 2750/4000 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUH2348-ECMH-PEX", "SKF NUH 2348 ECMH/PEX" ], "locale_variants": {} }, { "sku": "NUP1017-ML", "brand": "SKF", "manufacturer_designation": "SKF NUP 1017 ML", "series": "NUP1000-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 130, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 68.2, "static_load_kN": 86.5, "fatigue_load_limit_kN": 10.8, "max_rpm": 9000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 9000, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 85 mm shaft, SKF lists NUP1017-ML as single-row caged cylindrical roller: 130 mm OD, 22 mm wide, Pu 10.8 kN, the catalogue lists 6,000 r/min thermal reference speed and 9,000 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NUP1017-ML: the catalogue lists 6,000 r/min thermal reference speed and 9,000 r/min mechanical limiting speed. The mass entry 1100 g covers the complete catalogue execution. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 85 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1017, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 1017 ML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 22 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 130 mm raceway.", "The 68.2/86.5 kN ratings are SKF catalogue 17000 (2018) values for the ML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP1017-ML?", "a": "SKF NUP 1017 ML is a single-row caged cylindrical roller bearing with 85 mm bore, 130 mm OD and 22 mm width per ISO 15. SKF lists C 68.2 kN, C0 86.5 kN, Pu 10.8 kN, reference speed 6,000 r/min and limiting speed 9,000 r/min, mass about 1100 g." }, { "q": "What does the NUP designation and ML suffix mean?", "a": "The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP1017-ML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP1017-ML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP1017", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×130×22 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ1017-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×130×22 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU1017-ML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×130×22 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP1017-ML", "SKF NUP 1017 ML" ], "locale_variants": {} }, { "sku": "NUP1880-MP", "brand": "SKF", "manufacturer_designation": "SKF NUP 1880 MP", "series": "NUP1800-series", "type": "cylindrical_roller", "d_mm": 400, "D_mm": 500, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 572, "static_load_kN": 1180, "fatigue_load_limit_kN": 96.5, "max_rpm": 1900, "reference_speed_rpm": 1300, "limiting_speed_rpm": 1900, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP1880-MP is the 400 mm bore entry in the NUP1800 range: a 400×500×46 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 572 kN / C0 1180 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The MP suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. The radial section height is 50.0 mm and the catalogue mass 22500 g; at 572 kN dynamic rating this is roughly 1.43 kN of C per millimetre of bore before application factors. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 400 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 18 (ultra-slim section for large shafts) envelope is shared with the N/NU/NJ/NUP executions of 1880, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 1880 MP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "The 572/1180 kN ratings are SKF catalogue 17000 (2018) values for the MP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP1880-MP?", "a": "SKF NUP 1880 MP is a single-row caged cylindrical roller bearing with 400 mm bore, 500 mm OD and 46 mm width per ISO 15. SKF lists C 572 kN, C0 1180 kN, Pu 96.5 kN, reference speed 1,300 r/min and limiting speed 1,900 r/min, mass about 22500 g." }, { "q": "What does the NUP designation and MP suffix mean?", "a": "The MP suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP1880-MP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP1880-MP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ1880-MP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU1880-MP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 400×500×46 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP1880-MP", "SKF NUP 1880 MP" ], "locale_variants": {} }, { "sku": "NUP203-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 203 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 17, "D_mm": 40, "B_mm": 12, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 20, "static_load_kN": 14.3, "fatigue_load_limit_kN": 1.73, "max_rpm": 22000, "reference_speed_rpm": 20000, "limiting_speed_rpm": 22000, "weight_g": 72, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 203 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 17×40×12 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 72 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 11.5 mm and the catalogue mass 72 g; at 20 kN dynamic rating this is roughly 1.18 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "light gearbox layshafts", "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 203, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 203 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 40 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 40 mm raceway.", "The 20/14.3 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP203-ECP?", "a": "SKF NUP 203 ECP is a single-row caged cylindrical roller bearing with 17 mm bore, 40 mm OD and 12 mm width per ISO 15. SKF lists C 20 kN, C0 14.3 kN, Pu 1.73 kN, reference speed 20,000 r/min and limiting speed 22,000 r/min, mass about 72 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP203-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP203-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×12 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP203-ECP", "SKF NUP 203 ECP" ], "locale_variants": {} }, { "sku": "NUP204-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 204 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 47, "B_mm": 14, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 28.5, "static_load_kN": 22, "fatigue_load_limit_kN": 2.75, "max_rpm": 19000, "reference_speed_rpm": 17000, "limiting_speed_rpm": 19000, "weight_g": 120, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 204 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 20×47×14 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 120 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 28.5 kN and C0 22 kN, size the bearing on the 20×47 mm ISO 15 envelope and check the 2.75 kN Pu against the equivalent-load floor; the catalogue lists 17,000 r/min thermal reference speed and 19,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 20 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 204, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 204 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 14 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 47 mm raceway.", "The 28.5/22 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP204-ECP?", "a": "SKF NUP 204 ECP is a single-row caged cylindrical roller bearing with 20 mm bore, 47 mm OD and 14 mm width per ISO 15. SKF lists C 28.5 kN, C0 22 kN, Pu 2.75 kN, reference speed 17,000 r/min and limiting speed 19,000 r/min, mass about 120 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP204-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP204-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N204-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×47×14 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ204-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×47×14 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU204", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×47×14 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP204-ECP", "SKF NUP 204 ECP" ], "locale_variants": {} }, { "sku": "NUP205-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 205 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 52, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 32.5, "static_load_kN": 27, "fatigue_load_limit_kN": 3.35, "max_rpm": 16000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 16000, "weight_g": 140, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 205 ECP resolves to a 25×52×15 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NUP205-ECP: the catalogue lists 15,000 r/min thermal reference speed and 16,000 r/min mechanical limiting speed. The mass entry 140 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 205, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 205 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 52 mm raceway.", "The 32.5/27 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP205-ECP?", "a": "SKF NUP 205 ECP is a single-row caged cylindrical roller bearing with 25 mm bore, 52 mm OD and 15 mm width per ISO 15. SKF lists C 32.5 kN, C0 27 kN, Pu 3.35 kN, reference speed 15,000 r/min and limiting speed 16,000 r/min, mass about 140 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP205-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP205-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N205-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×52×15 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ205-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×52×15 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU205", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×52×15 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP205-ECP", "SKF NUP 205 ECP" ], "locale_variants": {} }, { "sku": "NUP206-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 206 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 62, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 44, "static_load_kN": 36.5, "fatigue_load_limit_kN": 4.55, "max_rpm": 14000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 14000, "weight_g": 210, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 206 ECP resolves to a 30×62×16 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 0.83 (36.5 against 44 kN), and the Pu figure 4.55 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 13,000 r/min thermal reference speed and 14,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 30 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 206, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 206 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 16 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 62 mm raceway.", "The 44/36.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP206-ECP?", "a": "SKF NUP 206 ECP is a single-row caged cylindrical roller bearing with 30 mm bore, 62 mm OD and 16 mm width per ISO 15. SKF lists C 44 kN, C0 36.5 kN, Pu 4.55 kN, reference speed 13,000 r/min and limiting speed 14,000 r/min, mass about 210 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP206-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP206-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N206-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×62×16 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ206-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×62×16 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU206", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×62×16 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP206-ECP", "SKF NUP 206 ECP" ], "locale_variants": {} }, { "sku": "NUP207-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 207 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 72, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 56, "static_load_kN": 48, "fatigue_load_limit_kN": 6.1, "max_rpm": 12000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 12000, "weight_g": 310, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP207-ECP is the 35 mm bore entry in the NUP200 range: a 35×72×17 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 56 kN / C0 48 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 18.5 mm and the catalogue mass 310 g; at 56 kN dynamic rating this is roughly 1.60 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 207, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 207 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 72 mm raceway.", "The 56/48 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP207-ECP?", "a": "SKF NUP 207 ECP is a single-row caged cylindrical roller bearing with 35 mm bore, 72 mm OD and 17 mm width per ISO 15. SKF lists C 56 kN, C0 48 kN, Pu 6.1 kN, reference speed 11,000 r/min and limiting speed 12,000 r/min, mass about 310 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP207-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP207-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N207-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×72×17 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ207-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×72×17 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU207", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×72×17 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP207-ECP", "SKF NUP 207 ECP" ], "locale_variants": {} }, { "sku": "NUP208-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 208 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 80, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 62, "static_load_kN": 53, "fatigue_load_limit_kN": 6.7, "max_rpm": 11000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 11000, "weight_g": 390, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 40 mm shaft, SKF lists NUP208-ECP as single-row caged cylindrical roller: 80 mm OD, 18 mm wide, Pu 6.7 kN, the catalogue lists 9,500 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 62 kN and C0 53 kN, size the bearing on the 40×80 mm ISO 15 envelope and check the 6.7 kN Pu against the equivalent-load floor; the catalogue lists 9,500 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. Fit practice for NUP208-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 208, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 208 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 80 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 80 mm raceway.", "The 62/53 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP208-ECP?", "a": "SKF NUP 208 ECP is a single-row caged cylindrical roller bearing with 40 mm bore, 80 mm OD and 18 mm width per ISO 15. SKF lists C 62 kN, C0 53 kN, Pu 6.7 kN, reference speed 9,500 r/min and limiting speed 11,000 r/min, mass about 390 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP208-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP208-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP208", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×80×18 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N208-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×80×18 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ208-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×80×18 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU208", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×80×18 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP208-ECP", "SKF NUP 208 ECP" ], "locale_variants": {} }, { "sku": "NUP209-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 209 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 85, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 69.5, "static_load_kN": 64, "fatigue_load_limit_kN": 8.15, "max_rpm": 9500, "reference_speed_rpm": 9000, "limiting_speed_rpm": 9500, "weight_g": 440, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 45 mm shaft, SKF lists NUP209-ECP as single-row caged cylindrical roller: 85 mm OD, 19 mm wide, Pu 8.15 kN, the catalogue lists 9,000 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NUP209-ECP: the catalogue lists 9,000 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. The mass entry 440 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 209, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 209 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 19 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 85 mm raceway.", "The 69.5/64 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP209-ECP?", "a": "SKF NUP 209 ECP is a single-row caged cylindrical roller bearing with 45 mm bore, 85 mm OD and 19 mm width per ISO 15. SKF lists C 69.5 kN, C0 64 kN, Pu 8.15 kN, reference speed 9,000 r/min and limiting speed 9,500 r/min, mass about 440 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP209-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP209-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP209", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×85×19 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N209-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×85×19 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ209-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×85×19 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU209", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×85×19 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP209-ECP", "SKF NUP 209 ECP" ], "locale_variants": {} }, { "sku": "NUP210-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 210 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 90, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 73.5, "static_load_kN": 69.5, "fatigue_load_limit_kN": 8.8, "max_rpm": 9000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 9000, "weight_g": 500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP210-ECP is the 50 mm bore entry in the NUP200 range: a 50×90×20 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 73.5 kN / C0 69.5 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP210-ECP: the catalogue lists 8,500 r/min thermal reference speed and 9,000 r/min mechanical limiting speed. The mass entry 500 g covers the complete catalogue execution. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 50 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 210, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 210 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 73.5/69.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP210-ECP?", "a": "SKF NUP 210 ECP is a single-row caged cylindrical roller bearing with 50 mm bore, 90 mm OD and 20 mm width per ISO 15. SKF lists C 73.5 kN, C0 69.5 kN, Pu 8.8 kN, reference speed 8,500 r/min and limiting speed 9,000 r/min, mass about 500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP210-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP210-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP210", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×90×20 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N210-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×90×20 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ210-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×90×20 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU210", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×90×20 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP210-ECP", "SKF NUP 210 ECP" ], "locale_variants": {} }, { "sku": "NUP211-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 211 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 100, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 96.5, "static_load_kN": 95, "fatigue_load_limit_kN": 12.2, "max_rpm": 8000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 8000, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP211-ECP is the 55 mm bore entry in the NUP200 range: a 55×100×21 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 96.5 kN / C0 95 kN. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 55 mm seat is about 1.75 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 95 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP211-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 211, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 211 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 21 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 96.5/95 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP211-ECP?", "a": "SKF NUP 211 ECP is a single-row caged cylindrical roller bearing with 55 mm bore, 100 mm OD and 21 mm width per ISO 15. SKF lists C 96.5 kN, C0 95 kN, Pu 12.2 kN, reference speed 7,500 r/min and limiting speed 8,000 r/min, mass about 680 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP211-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP211-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP211", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×100×21 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N211-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×100×21 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ211-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×100×21 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU211", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×100×21 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP211-ECP", "SKF NUP 211 ECP" ], "locale_variants": {} }, { "sku": "NUP212-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 212 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 110, "B_mm": 22, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 108, "static_load_kN": 102, "fatigue_load_limit_kN": 13.4, "max_rpm": 7500, "reference_speed_rpm": 6700, "limiting_speed_rpm": 7500, "weight_g": 860, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 60 mm shaft, SKF lists NUP212-ECP as single-row caged cylindrical roller: 110 mm OD, 22 mm wide, Pu 13.4 kN, the catalogue lists 6,700 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 25.0 mm and the catalogue mass 860 g; at 108 kN dynamic rating this is roughly 1.80 kN of C per millimetre of bore before application factors. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 60 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 212, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 212 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 108/102 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP212-ECP?", "a": "SKF NUP 212 ECP is a single-row caged cylindrical roller bearing with 60 mm bore, 110 mm OD and 22 mm width per ISO 15. SKF lists C 108 kN, C0 102 kN, Pu 13.4 kN, reference speed 6,700 r/min and limiting speed 7,500 r/min, mass about 860 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP212-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP212-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP212", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×110×22 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N212-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×110×22 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ212-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×110×22 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU212", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×110×22 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP212-ECP", "SKF NUP 212 ECP" ], "locale_variants": {} }, { "sku": "NUP213-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 213 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 120, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 122, "static_load_kN": 118, "fatigue_load_limit_kN": 15.6, "max_rpm": 6700, "reference_speed_rpm": 6300, "limiting_speed_rpm": 6700, "weight_g": 1050, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 65 mm shaft, SKF lists NUP213-ECP as single-row caged cylindrical roller: 120 mm OD, 23 mm wide, Pu 15.6 kN, the catalogue lists 6,300 r/min thermal reference speed and 6,700 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 122 kN and C0 118 kN, size the bearing on the 65×120 mm ISO 15 envelope and check the 15.6 kN Pu against the equivalent-load floor; the catalogue lists 6,300 r/min thermal reference speed and 6,700 r/min mechanical limiting speed. Fit practice for NUP213-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 213, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 213 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 23 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 122/118 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP213-ECP?", "a": "SKF NUP 213 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 120 mm OD and 23 mm width per ISO 15. SKF lists C 122 kN, C0 118 kN, Pu 15.6 kN, reference speed 6,300 r/min and limiting speed 6,700 r/min, mass about 1050 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP213-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP213-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP213", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×120×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×23 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU213", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP213-ECP", "SKF NUP 213 ECP" ], "locale_variants": {} }, { "sku": "NUP214-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 214 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 125, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 137, "static_load_kN": 137, "fatigue_load_limit_kN": 18, "max_rpm": 6300, "reference_speed_rpm": 6000, "limiting_speed_rpm": 6300, "weight_g": 1200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 214 ECP is a single-row caged cylindrical roller bearing sized 70×125×24 mm — a dimension series 2 (light-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP214-ECP: the catalogue lists 6,000 r/min thermal reference speed and 6,300 r/min mechanical limiting speed. The mass entry 1200 g covers the complete catalogue execution. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 214, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 214 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 137/137 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP214-ECP?", "a": "SKF NUP 214 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 125 mm OD and 24 mm width per ISO 15. SKF lists C 137 kN, C0 137 kN, Pu 18 kN, reference speed 6,000 r/min and limiting speed 6,300 r/min, mass about 1200 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP214-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP214-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP214", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×125×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×24 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×24 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU214", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×24 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP214-ECP", "SKF NUP 214 ECP" ], "locale_variants": {} }, { "sku": "NUP215-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 215 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 130, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 150, "static_load_kN": 156, "fatigue_load_limit_kN": 20.4, "max_rpm": 6000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6000, "weight_g": 1300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 215 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 75×130×25 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 1300 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 75 mm seat is about 2.00 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 156 kN for static checks such as crane hook blocks standing under load. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 215, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 215 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 130 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 150/156 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP215-ECP?", "a": "SKF NUP 215 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 130 mm OD and 25 mm width per ISO 15. SKF lists C 150 kN, C0 156 kN, Pu 20.4 kN, reference speed 5,600 r/min and limiting speed 6,000 r/min, mass about 1300 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP215-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP215-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP215", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×130×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×25 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×25 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU215", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×25 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP215-ECP", "SKF NUP 215 ECP" ], "locale_variants": {} }, { "sku": "NUP216-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 216 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 140, "B_mm": 26, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 160, "static_load_kN": 166, "fatigue_load_limit_kN": 21.2, "max_rpm": 5600, "reference_speed_rpm": 5300, "limiting_speed_rpm": 5600, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 216 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 80×140×26 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 1550 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.04 (166 against 160 kN), and the Pu figure 21.2 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 5,300 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 216, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 216 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 26 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 160/166 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP216-ECP?", "a": "SKF NUP 216 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 140 mm OD and 26 mm width per ISO 15. SKF lists C 160 kN, C0 166 kN, Pu 21.2 kN, reference speed 5,300 r/min and limiting speed 5,600 r/min, mass about 1550 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP216-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP216-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP216", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×140×26 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×26 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×26 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU216", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×26 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP216-ECP", "SKF NUP 216 ECP" ], "locale_variants": {} }, { "sku": "NUP217-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 217 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 150, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 190, "static_load_kN": 200, "fatigue_load_limit_kN": 25, "max_rpm": 5300, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5300, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 217 ECP resolves to a 85×150×28 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 32.5 mm and the catalogue mass 1900 g; at 190 kN dynamic rating this is roughly 2.24 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 217, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 217 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 190/200 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP217-ECP?", "a": "SKF NUP 217 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 150 mm OD and 28 mm width per ISO 15. SKF lists C 190 kN, C0 200 kN, Pu 25 kN, reference speed 4,800 r/min and limiting speed 5,300 r/min, mass about 1900 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP217-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP217-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP217", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×150×28 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×28 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×28 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU217", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×28 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP217-ECP", "SKF NUP 217 ECP" ], "locale_variants": {} }, { "sku": "NUP218-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 218 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 160, "B_mm": 30, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 208, "static_load_kN": 220, "fatigue_load_limit_kN": 27, "max_rpm": 5000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5000, "weight_g": 2450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 218 ECP resolves to a 90×160×30 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 208 kN and C0 220 kN, size the bearing on the 90×160 mm ISO 15 envelope and check the 27 kN Pu against the equivalent-load floor; the catalogue lists 4,500 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 218, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 218 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 160 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 208/220 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP218-ECP?", "a": "SKF NUP 218 ECP is a single-row caged cylindrical roller bearing with 90 mm bore, 160 mm OD and 30 mm width per ISO 15. SKF lists C 208 kN, C0 220 kN, Pu 27 kN, reference speed 4,500 r/min and limiting speed 5,000 r/min, mass about 2450 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP218-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP218-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP218", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×160×30 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×30 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×30 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU218", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×30 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP218-ECP", "SKF NUP 218 ECP" ], "locale_variants": {} }, { "sku": "NUP219-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 219 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 170, "B_mm": 32, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 255, "static_load_kN": 265, "fatigue_load_limit_kN": 32.5, "max_rpm": 4800, "reference_speed_rpm": 4300, "limiting_speed_rpm": 4800, "weight_g": 2900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP219-ECP is the 95 mm bore entry in the NUP200 range: a 95×170×32 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 255 kN / C0 265 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 95 mm seat is about 2.68 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 265 kN for static checks such as crane hook blocks standing under load. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 219, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 219 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 255/265 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP219-ECP?", "a": "SKF NUP 219 ECP is a single-row caged cylindrical roller bearing with 95 mm bore, 170 mm OD and 32 mm width per ISO 15. SKF lists C 255 kN, C0 265 kN, Pu 32.5 kN, reference speed 4,300 r/min and limiting speed 4,800 r/min, mass about 2900 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP219-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP219-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP219", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×170×32 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×32 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×32 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU219", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×32 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP219-ECP", "SKF NUP 219 ECP" ], "locale_variants": {} }, { "sku": "NUP220-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 220 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 180, "B_mm": 34, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 285, "static_load_kN": 305, "fatigue_load_limit_kN": 36.5, "max_rpm": 4500, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4500, "weight_g": 3600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 220 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 100×180×34 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 3600 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.07 (305 against 285 kN), and the Pu figure 36.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,000 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 100 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 220, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 220 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 34 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 285/305 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP220-ECP?", "a": "SKF NUP 220 ECP is a single-row caged cylindrical roller bearing with 100 mm bore, 180 mm OD and 34 mm width per ISO 15. SKF lists C 285 kN, C0 305 kN, Pu 36.5 kN, reference speed 4,000 r/min and limiting speed 4,500 r/min, mass about 3600 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP220-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP220-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP220", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×180×34 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×34 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×34 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU220", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×34 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP220-ECP", "SKF NUP 220 ECP" ], "locale_variants": {} }, { "sku": "NUP2203-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2203 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 17, "D_mm": 40, "B_mm": 16, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 27.5, "static_load_kN": 21.6, "fatigue_load_limit_kN": 2.65, "max_rpm": 22000, "reference_speed_rpm": 20000, "limiting_speed_rpm": 22000, "weight_g": 97, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 17 mm shaft, SKF lists NUP2203-ECP as single-row caged cylindrical roller: 40 mm OD, 16 mm wide, Pu 2.65 kN, the catalogue lists 20,000 r/min thermal reference speed and 22,000 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 0.79 (21.6 against 27.5 kN), and the Pu figure 2.65 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 20,000 r/min thermal reference speed and 22,000 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions", "appliance and fan armature shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2203, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2203 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 16 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 27.5/21.6 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2203-ECP?", "a": "SKF NUP 2203 ECP is a single-row caged cylindrical roller bearing with 17 mm bore, 40 mm OD and 16 mm width per ISO 15. SKF lists C 27.5 kN, C0 21.6 kN, Pu 2.65 kN, reference speed 20,000 r/min and limiting speed 22,000 r/min, mass about 97 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2203-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2203-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×16 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2203-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 17×40×16 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2203-ECP", "SKF NUP 2203 ECP" ], "locale_variants": {} }, { "sku": "NUP2205-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2205 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 52, "B_mm": 18, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 39, "static_load_kN": 34, "fatigue_load_limit_kN": 4.25, "max_rpm": 16000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 16000, "weight_g": 170, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2205 ECP is a single-row caged cylindrical roller bearing sized 25×52×18 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP2205-ECP: the catalogue lists 15,000 r/min thermal reference speed and 16,000 r/min mechanical limiting speed. The mass entry 170 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2205, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2205 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 18 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 39/34 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2205-ECP?", "a": "SKF NUP 2205 ECP is a single-row caged cylindrical roller bearing with 25 mm bore, 52 mm OD and 18 mm width per ISO 15. SKF lists C 39 kN, C0 34 kN, Pu 4.25 kN, reference speed 15,000 r/min and limiting speed 16,000 r/min, mass about 170 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2205-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2205-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2205-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×52×18 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2205", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×52×18 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2205-ECP", "SKF NUP 2205 ECP" ], "locale_variants": {} }, { "sku": "NUP2206-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2206 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 62, "B_mm": 20, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 55, "static_load_kN": 49, "fatigue_load_limit_kN": 6.1, "max_rpm": 14000, "reference_speed_rpm": 13000, "limiting_speed_rpm": 14000, "weight_g": 270, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2206 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 30×62×20 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 270 g. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 30 mm seat is about 1.83 kN/mm, typical of dimension series 22 (light-section, wide); use C0 49 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2206-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2206, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2206 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 55/49 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2206-ECP?", "a": "SKF NUP 2206 ECP is a single-row caged cylindrical roller bearing with 30 mm bore, 62 mm OD and 20 mm width per ISO 15. SKF lists C 55 kN, C0 49 kN, Pu 6.1 kN, reference speed 13,000 r/min and limiting speed 14,000 r/min, mass about 270 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2206-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2206-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2206-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×62×20 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2206", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×62×20 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2206-ECP", "SKF NUP 2206 ECP" ], "locale_variants": {} }, { "sku": "NUP2207-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2207 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 72, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 69.5, "static_load_kN": 63, "fatigue_load_limit_kN": 8.15, "max_rpm": 12000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 12000, "weight_g": 420, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2207 ECP resolves to a 35×72×23 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 0.91 (63 against 69.5 kN), and the Pu figure 8.15 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 11,000 r/min thermal reference speed and 12,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 35 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2207, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2207 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 72 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 69.5/63 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2207-ECP?", "a": "SKF NUP 2207 ECP is a single-row caged cylindrical roller bearing with 35 mm bore, 72 mm OD and 23 mm width per ISO 15. SKF lists C 69.5 kN, C0 63 kN, Pu 8.15 kN, reference speed 11,000 r/min and limiting speed 12,000 r/min, mass about 420 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2207-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2207-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2207-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×72×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2207", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×72×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2207-ECP", "SKF NUP 2207 ECP" ], "locale_variants": {} }, { "sku": "NUP2208-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2208 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 80, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 81.5, "static_load_kN": 75, "fatigue_load_limit_kN": 9.65, "max_rpm": 11000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 11000, "weight_g": 510, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2208 ECP resolves to a 40×80×23 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 20.0 mm and the catalogue mass 510 g; at 81.5 kN dynamic rating this is roughly 2.04 kN of C per millimetre of bore before application factors. Fit practice for NUP2208-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2208, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2208 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 23 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 81.5/75 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2208-ECP?", "a": "SKF NUP 2208 ECP is a single-row caged cylindrical roller bearing with 40 mm bore, 80 mm OD and 23 mm width per ISO 15. SKF lists C 81.5 kN, C0 75 kN, Pu 9.65 kN, reference speed 9,500 r/min and limiting speed 11,000 r/min, mass about 510 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2208-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2208-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2208", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×80×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2208-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×80×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2208", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×80×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2208-ECP", "SKF NUP 2208 ECP" ], "locale_variants": {} }, { "sku": "NUP2209-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2209 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 85, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 85, "static_load_kN": 81.5, "fatigue_load_limit_kN": 10.6, "max_rpm": 9500, "reference_speed_rpm": 9000, "limiting_speed_rpm": 9500, "weight_g": 550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2209-ECP is the 45 mm bore entry in the NUP2200 range: a 45×85×23 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 85 kN / C0 81.5 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 20.0 mm and the catalogue mass 550 g; at 85 kN dynamic rating this is roughly 1.89 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2209, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2209 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 85 mm raceway.", "The 85/81.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2209-ECP?", "a": "SKF NUP 2209 ECP is a single-row caged cylindrical roller bearing with 45 mm bore, 85 mm OD and 23 mm width per ISO 15. SKF lists C 85 kN, C0 81.5 kN, Pu 10.6 kN, reference speed 9,000 r/min and limiting speed 9,500 r/min, mass about 550 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2209-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2209-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2209", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×85×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2209-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×85×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2209", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×85×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2209-ECP", "SKF NUP 2209 ECP" ], "locale_variants": {} }, { "sku": "NUP221-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 221 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 105, "D_mm": 190, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 300, "static_load_kN": 315, "fatigue_load_limit_kN": 36.5, "max_rpm": 4300, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4300, "weight_g": 4200, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 221 ECP resolves to a 105×190×36 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 42.5 mm and the catalogue mass 4200 g; at 300 kN dynamic rating this is roughly 2.86 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 221, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 221 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 300/315 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP221-ECP?", "a": "SKF NUP 221 ECP is a single-row caged cylindrical roller bearing with 105 mm bore, 190 mm OD and 36 mm width per ISO 15. SKF lists C 300 kN, C0 315 kN, Pu 36.5 kN, reference speed 3,800 r/min and limiting speed 4,300 r/min, mass about 4200 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP221-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP221-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP221", "equiv_brand": "NTN", "level": "partial", "note": "Same 105×190×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU221-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 105×190×36 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP221-ECP", "SKF NUP 221 ECP" ], "locale_variants": {} }, { "sku": "NUP2210-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2210 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 90, "static_load_kN": 88, "fatigue_load_limit_kN": 11.4, "max_rpm": 9000, "reference_speed_rpm": 8500, "limiting_speed_rpm": 9000, "weight_g": 590, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2210 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 50×90×23 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 590 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 90 kN and C0 88 kN, size the bearing on the 50×90 mm ISO 15 envelope and check the 11.4 kN Pu against the equivalent-load floor; the catalogue lists 8,500 r/min thermal reference speed and 9,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 50 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2210, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2210 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 23 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 23 mm-wide ring and concentrates load.", "The 90/88 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2210-ECP?", "a": "SKF NUP 2210 ECP is a single-row caged cylindrical roller bearing with 50 mm bore, 90 mm OD and 23 mm width per ISO 15. SKF lists C 90 kN, C0 88 kN, Pu 11.4 kN, reference speed 8,500 r/min and limiting speed 9,000 r/min, mass about 590 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2210-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2210-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2210", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×90×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2210-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×90×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2210", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×90×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2210-ECP", "SKF NUP 2210 ECP" ], "locale_variants": {} }, { "sku": "NUP2211-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2211 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 100, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 114, "static_load_kN": 118, "fatigue_load_limit_kN": 15.3, "max_rpm": 8000, "reference_speed_rpm": 7500, "limiting_speed_rpm": 8000, "weight_g": 820, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2211 ECP resolves to a 55×100×25 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP2211-ECP: the catalogue lists 7,500 r/min thermal reference speed and 8,000 r/min mechanical limiting speed. The mass entry 820 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2211, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2211 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 25 mm-wide ring and concentrates load.", "The 114/118 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2211-ECP?", "a": "SKF NUP 2211 ECP is a single-row caged cylindrical roller bearing with 55 mm bore, 100 mm OD and 25 mm width per ISO 15. SKF lists C 114 kN, C0 118 kN, Pu 15.3 kN, reference speed 7,500 r/min and limiting speed 8,000 r/min, mass about 820 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2211-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2211-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2211", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×100×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2211-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×100×25 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2211", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×100×25 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2211-ECP", "SKF NUP 2211 ECP" ], "locale_variants": {} }, { "sku": "NUP2212-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2212 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 110, "B_mm": 28, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 146, "static_load_kN": 153, "fatigue_load_limit_kN": 20, "max_rpm": 7500, "reference_speed_rpm": 6700, "limiting_speed_rpm": 7500, "weight_g": 1100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2212 ECP resolves to a 60×110×28 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 1.05 (153 against 146 kN), and the Pu figure 20 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 6,700 r/min thermal reference speed and 7,500 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 60 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2212, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2212 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 28 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 28 mm-wide ring and concentrates load.", "The 146/153 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2212-ECP?", "a": "SKF NUP 2212 ECP is a single-row caged cylindrical roller bearing with 60 mm bore, 110 mm OD and 28 mm width per ISO 15. SKF lists C 146 kN, C0 153 kN, Pu 20 kN, reference speed 6,700 r/min and limiting speed 7,500 r/min, mass about 1100 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2212-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2212-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2212", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×110×28 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2212-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×110×28 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2212", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×110×28 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2212-ECP", "SKF NUP 2212 ECP" ], "locale_variants": {} }, { "sku": "NUP2213-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2213 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 120, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 170, "static_load_kN": 180, "fatigue_load_limit_kN": 24, "max_rpm": 6700, "reference_speed_rpm": 6300, "limiting_speed_rpm": 6700, "weight_g": 1450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2213-ECP is the 65 mm bore entry in the NUP2200 range: a 65×120×31 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 170 kN / C0 180 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 27.5 mm and the catalogue mass 1450 g; at 170 kN dynamic rating this is roughly 2.62 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2213, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2213 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 170/180 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2213-ECP?", "a": "SKF NUP 2213 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 120 mm OD and 31 mm width per ISO 15. SKF lists C 170 kN, C0 180 kN, Pu 24 kN, reference speed 6,300 r/min and limiting speed 6,700 r/min, mass about 1450 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2213-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2213-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2213", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×120×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2213-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×120×31 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2213-ECP", "SKF NUP 2213 ECP" ], "locale_variants": {} }, { "sku": "NUP2214-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2214 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 125, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 180, "static_load_kN": 193, "fatigue_load_limit_kN": 25.5, "max_rpm": 6300, "reference_speed_rpm": 6000, "limiting_speed_rpm": 6300, "weight_g": 1550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2214-ECP is the 70 mm bore entry in the NUP2200 range: a 70×125×31 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 180 kN / C0 193 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 180 kN and C0 193 kN, size the bearing on the 70×125 mm ISO 15 envelope and check the 25.5 kN Pu against the equivalent-load floor; the catalogue lists 6,000 r/min thermal reference speed and 6,300 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2214, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2214 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 125 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 180/193 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2214-ECP?", "a": "SKF NUP 2214 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 125 mm OD and 31 mm width per ISO 15. SKF lists C 180 kN, C0 193 kN, Pu 25.5 kN, reference speed 6,000 r/min and limiting speed 6,300 r/min, mass about 1550 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2214-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2214-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2214", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×125×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2214-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×125×31 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2214-ECP", "SKF NUP 2214 ECP" ], "locale_variants": {} }, { "sku": "NUP2215-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2215 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 130, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 186, "static_load_kN": 208, "fatigue_load_limit_kN": 27, "max_rpm": 6000, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6000, "weight_g": 1600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 75 mm shaft, SKF lists NUP2215-ECP as single-row caged cylindrical roller: 130 mm OD, 31 mm wide, Pu 27 kN, the catalogue lists 5,600 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP2215-ECP: the catalogue lists 5,600 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. The mass entry 1600 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2215, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2215 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 186/208 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2215-ECP?", "a": "SKF NUP 2215 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 130 mm OD and 31 mm width per ISO 15. SKF lists C 186 kN, C0 208 kN, Pu 27 kN, reference speed 5,600 r/min and limiting speed 6,000 r/min, mass about 1600 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2215-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2215-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2215", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×130×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2215-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×130×31 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2215-ECP", "SKF NUP 2215 ECP" ], "locale_variants": {} }, { "sku": "NUP2216-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2216 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 212, "static_load_kN": 245, "fatigue_load_limit_kN": 31, "max_rpm": 5600, "reference_speed_rpm": 5300, "limiting_speed_rpm": 5600, "weight_g": 2000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2216 ECP is a single-row caged cylindrical roller bearing sized 80×140×33 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 80 mm seat is about 2.65 kN/mm, typical of dimension series 22 (light-section, wide); use C0 245 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2216-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2216, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2216 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 33 mm-wide ring and concentrates load.", "The 212/245 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2216-ECP?", "a": "SKF NUP 2216 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 140 mm OD and 33 mm width per ISO 15. SKF lists C 212 kN, C0 245 kN, Pu 31 kN, reference speed 5,300 r/min and limiting speed 5,600 r/min, mass about 2000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2216-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2216-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2216", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×140×33 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2216-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×140×33 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2216-ECP", "SKF NUP 2216 ECP" ], "locale_variants": {} }, { "sku": "NUP2217-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2217 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 150, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 250, "static_load_kN": 280, "fatigue_load_limit_kN": 34.5, "max_rpm": 5300, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5300, "weight_g": 2600, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2217 ECP is a single-row caged cylindrical roller bearing sized 85×150×36 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.12 (280 against 250 kN), and the Pu figure 34.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,800 r/min thermal reference speed and 5,300 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2217, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2217 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 36 mm-wide ring and concentrates load.", "The 250/280 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2217-ECP?", "a": "SKF NUP 2217 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 150 mm OD and 36 mm width per ISO 15. SKF lists C 250 kN, C0 280 kN, Pu 34.5 kN, reference speed 4,800 r/min and limiting speed 5,300 r/min, mass about 2600 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2217-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2217-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2217", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×150×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×36 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2217-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×150×36 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2217-ECP", "SKF NUP 2217 ECP" ], "locale_variants": {} }, { "sku": "NUP2218-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2218 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 160, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 280, "static_load_kN": 315, "fatigue_load_limit_kN": 39, "max_rpm": 5000, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5000, "weight_g": 3300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2218 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 90×160×40 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 3300 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 35.0 mm and the catalogue mass 3300 g; at 280 kN dynamic rating this is roughly 3.11 kN of C per millimetre of bore before application factors. Fit practice for NUP2218-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2218, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2218 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 280/315 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2218-ECP?", "a": "SKF NUP 2218 ECP is a single-row caged cylindrical roller bearing with 90 mm bore, 160 mm OD and 40 mm width per ISO 15. SKF lists C 280 kN, C0 315 kN, Pu 39 kN, reference speed 4,500 r/min and limiting speed 5,000 r/min, mass about 3300 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2218-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2218-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2218", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×160×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2218-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×160×40 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2218-ECP", "SKF NUP 2218 ECP" ], "locale_variants": {} }, { "sku": "NUP2219-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2219 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 170, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 325, "static_load_kN": 375, "fatigue_load_limit_kN": 45.5, "max_rpm": 4800, "reference_speed_rpm": 4300, "limiting_speed_rpm": 4800, "weight_g": 4000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2219 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 95×170×43 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 4000 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP2219-ECP: the catalogue lists 4,300 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. The mass entry 4000 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2219, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2219 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 43 mm-wide ring and concentrates load.", "The 325/375 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2219-ECP?", "a": "SKF NUP 2219 ECP is a single-row caged cylindrical roller bearing with 95 mm bore, 170 mm OD and 43 mm width per ISO 15. SKF lists C 325 kN, C0 375 kN, Pu 45.5 kN, reference speed 4,300 r/min and limiting speed 4,800 r/min, mass about 4000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2219-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2219-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2219", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×170×43 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×43 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2219-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×170×43 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2219-ECP", "SKF NUP 2219 ECP" ], "locale_variants": {} }, { "sku": "NUP222-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 222 ECP", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 200, "B_mm": 38, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 335, "static_load_kN": 365, "fatigue_load_limit_kN": 42.5, "max_rpm": 4000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4000, "weight_g": 5000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 222 ECP resolves to a 110×200×38 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 335 kN and C0 365 kN, size the bearing on the 110×200 mm ISO 15 envelope and check the 42.5 kN Pu against the equivalent-load floor; the catalogue lists 3,600 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 222, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 222 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 335/365 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP222-ECP?", "a": "SKF NUP 222 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 200 mm OD and 38 mm width per ISO 15. SKF lists C 335 kN, C0 365 kN, Pu 42.5 kN, reference speed 3,600 r/min and limiting speed 4,000 r/min, mass about 5000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP222-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP222-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP222", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×200×38 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×38 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP222-ECP", "SKF NUP 222 ECP" ], "locale_variants": {} }, { "sku": "NUP2220-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2220 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 180, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 380, "static_load_kN": 450, "fatigue_load_limit_kN": 54, "max_rpm": 4500, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4500, "weight_g": 4800, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2220 ECP is a single-row caged cylindrical roller bearing sized 100×180×46 mm — a dimension series 22 (light-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 100 mm seat is about 3.80 kN/mm, typical of dimension series 22 (light-section, wide); use C0 450 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2220-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2220, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2220 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 380/450 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2220-ECP?", "a": "SKF NUP 2220 ECP is a single-row caged cylindrical roller bearing with 100 mm bore, 180 mm OD and 46 mm width per ISO 15. SKF lists C 380 kN, C0 450 kN, Pu 54 kN, reference speed 4,000 r/min and limiting speed 4,500 r/min, mass about 4800 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2220-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2220-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2220", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×180×46 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2220-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×180×46 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2220-ECP", "SKF NUP 2220 ECP" ], "locale_variants": {} }, { "sku": "NUP2222-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2222 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 200, "B_mm": 53, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 440, "static_load_kN": 520, "fatigue_load_limit_kN": 61, "max_rpm": 4000, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4000, "weight_g": 7000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2222 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 110×200×53 mm envelope, dimension series 22 (light-section, wide), with catalogue mass 7000 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.18 (520 against 440 kN), and the Pu figure 61 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2222, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2222 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 53 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 440/520 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2222-ECP?", "a": "SKF NUP 2222 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 200 mm OD and 53 mm width per ISO 15. SKF lists C 440 kN, C0 520 kN, Pu 61 kN, reference speed 3,600 r/min and limiting speed 4,000 r/min, mass about 7000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2222-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2222-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2222", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×200×53 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×53 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2222-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×200×53 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2222-ECP", "SKF NUP 2222 ECP" ], "locale_variants": {} }, { "sku": "NUP2224-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2224 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 215, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 520, "static_load_kN": 630, "fatigue_load_limit_kN": 72, "max_rpm": 3600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3600, "weight_g": 8650, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2224 ECP resolves to a 120×215×58 mm single-row caged cylindrical roller bearing (dimension series 22 (light-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 520 kN and C0 630 kN, size the bearing on the 120×215 mm ISO 15 envelope and check the 72 kN Pu against the equivalent-load floor; the catalogue lists 3,400 r/min thermal reference speed and 3,600 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 120 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2224, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2224 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 520/630 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2224-ECP?", "a": "SKF NUP 2224 ECP is a single-row caged cylindrical roller bearing with 120 mm bore, 215 mm OD and 58 mm width per ISO 15. SKF lists C 520 kN, C0 630 kN, Pu 72 kN, reference speed 3,400 r/min and limiting speed 3,600 r/min, mass about 8650 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2224-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2224-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2224", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×215×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2224-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×58 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2224-ECP", "SKF NUP 2224 ECP" ], "locale_variants": {} }, { "sku": "NUP2226-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2226 ECP", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 230, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 610, "static_load_kN": 735, "fatigue_load_limit_kN": 83, "max_rpm": 3400, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3400, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2226-ECP is the 130 mm bore entry in the NUP2200 range: a 130×230×64 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 610 kN / C0 735 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.20 (735 against 610 kN), and the Pu figure 83 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,200 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2226, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2226 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 230 mm raceway.", "The 610/735 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2226-ECP?", "a": "SKF NUP 2226 ECP is a single-row caged cylindrical roller bearing with 130 mm bore, 230 mm OD and 64 mm width per ISO 15. SKF lists C 610 kN, C0 735 kN, Pu 83 kN, reference speed 3,200 r/min and limiting speed 3,400 r/min, mass about 10500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2226-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2226-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2226", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×230×64 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2226-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×64 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×64 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2226-ECP", "SKF NUP 2226 ECP" ], "locale_variants": {} }, { "sku": "NUP2228-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 2228 ECML", "series": "NUP2200-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 250, "B_mm": 68, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 655, "static_load_kN": 830, "fatigue_load_limit_kN": 93, "max_rpm": 4800, "reference_speed_rpm": 2800, "limiting_speed_rpm": 4800, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 140 mm shaft, SKF lists NUP2228-ECML as single-row caged cylindrical roller: 250 mm OD, 68 mm wide, Pu 93 kN, the catalogue lists 2,800 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 140 mm seat is about 4.68 kN/mm, typical of dimension series 22 (light-section, wide); use C0 830 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2228-ECML: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2228, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2228 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 655/830 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2228-ECML?", "a": "SKF NUP 2228 ECML is a single-row caged cylindrical roller bearing with 140 mm bore, 250 mm OD and 68 mm width per ISO 15. SKF lists C 655 kN, C0 830 kN, Pu 93 kN, reference speed 2,800 r/min and limiting speed 4,800 r/min, mass about 15500 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2228-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2228-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2228", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×250×68 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2228-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2228-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2228-ECML", "SKF NUP 2228 ECML" ], "locale_variants": {} }, { "sku": "NUP224-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 224 ECJ", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 215, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 390, "static_load_kN": 430, "fatigue_load_limit_kN": 49, "max_rpm": 3600, "reference_speed_rpm": 3400, "limiting_speed_rpm": 3600, "weight_g": 5950, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 224 ECJ denotes a single-row caged cylindrical roller bearing on the ISO 15 120×215×40 mm envelope, dimension series 2 (light-section ISO 15 envelope), with catalogue mass 5950 g. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECJ: the E-design execution with a pressed sheet-steel window cage, for positions where polymer cages are temperature- or lubricant-limited. Load-per-bore for the 120 mm seat is about 3.25 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 430 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP224-ECJ: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 224, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 224 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 215 mm raceway.", "The 390/430 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP224-ECJ?", "a": "SKF NUP 224 ECJ is a single-row caged cylindrical roller bearing with 120 mm bore, 215 mm OD and 40 mm width per ISO 15. SKF lists C 390 kN, C0 430 kN, Pu 49 kN, reference speed 3,400 r/min and limiting speed 3,600 r/min, mass about 5950 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP224-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP224-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP224", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×215×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU224-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×215×40 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP224-ECJ", "SKF NUP 224 ECJ" ], "locale_variants": {} }, { "sku": "NUP226-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 226 ECJ", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 230, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 415, "static_load_kN": 455, "fatigue_load_limit_kN": 51, "max_rpm": 3400, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3400, "weight_g": 6500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 226 ECJ resolves to a 130×230×40 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. The pressed sheet-steel window-type cage is reflected in the published speeds and temperature limits. The radial section height is 50.0 mm and the catalogue mass 6500 g; at 415 kN dynamic rating this is roughly 3.19 kN of C per millimetre of bore before application factors. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 226, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 226 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "The 415/455 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP226-ECJ?", "a": "SKF NUP 226 ECJ is a single-row caged cylindrical roller bearing with 130 mm bore, 230 mm OD and 40 mm width per ISO 15. SKF lists C 415 kN, C0 455 kN, Pu 51 kN, reference speed 3,200 r/min and limiting speed 3,400 r/min, mass about 6500 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP226-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP226-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP226", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×230×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU226-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×230×40 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP226-ECJ", "SKF NUP 226 ECJ" ], "locale_variants": {} }, { "sku": "NUP228-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 228 ECJ", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 250, "B_mm": 42, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 450, "static_load_kN": 510, "fatigue_load_limit_kN": 57, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 8450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP228-ECJ is the 140 mm bore entry in the NUP200 range: a 140×250×42 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 450 kN / C0 510 kN. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. The pressed sheet-steel window-type cage is reflected in the published speeds and temperature limits. Speed planning for NUP228-ECJ: the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. The mass entry 8450 g covers the complete catalogue execution. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 140 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 228, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 228 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 42 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 42 mm-wide ring and concentrates load.", "The 450/510 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP228-ECJ?", "a": "SKF NUP 228 ECJ is a single-row caged cylindrical roller bearing with 140 mm bore, 250 mm OD and 42 mm width per ISO 15. SKF lists C 450 kN, C0 510 kN, Pu 57 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 8450 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP228-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP228-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP228", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×250×42 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ228-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×42 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU228-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×250×42 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP228-ECJ", "SKF NUP 228 ECJ" ], "locale_variants": {} }, { "sku": "NUP230-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 230 ECJ", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 150, "D_mm": 270, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 510, "static_load_kN": 600, "fatigue_load_limit_kN": 64, "max_rpm": 2800, "reference_speed_rpm": 2600, "limiting_speed_rpm": 2800, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 230 ECJ resolves to a 150×270×45 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECJ: the E-design execution with a pressed sheet-steel window cage, for positions where polymer cages are temperature- or lubricant-limited. Selection arithmetic: C0/C ≈ 1.18 (600 against 510 kN), and the Pu figure 64 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,600 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 150 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 230, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 230 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 45 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 510/600 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP230-ECJ?", "a": "SKF NUP 230 ECJ is a single-row caged cylindrical roller bearing with 150 mm bore, 270 mm OD and 45 mm width per ISO 15. SKF lists C 510 kN, C0 600 kN, Pu 64 kN, reference speed 2,600 r/min and limiting speed 2,800 r/min, mass about 10500 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP230-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP230-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP230", "equiv_brand": "NTN", "level": "partial", "note": "Same 150×270×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ230-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×45 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU230-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 150×270×45 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP230-ECJ", "SKF NUP 230 ECJ" ], "locale_variants": {} }, { "sku": "NUP2304-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2304 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 52, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 47.5, "static_load_kN": 38, "fatigue_load_limit_kN": 4.8, "max_rpm": 18000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 18000, "weight_g": 220, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2304-ECP is the 20 mm bore entry in the NUP2300 range: a 20×52×21 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 47.5 kN / C0 38 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 47.5 kN and C0 38 kN, size the bearing on the 20×52 mm ISO 15 envelope and check the 4.8 kN Pu against the equivalent-load floor; the catalogue lists 15,000 r/min thermal reference speed and 18,000 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts", "small industrial electric-motor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2304, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2304 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 21 mm-wide ring and concentrates load.", "The 47.5/38 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2304-ECP?", "a": "SKF NUP 2304 ECP is a single-row caged cylindrical roller bearing with 20 mm bore, 52 mm OD and 21 mm width per ISO 15. SKF lists C 47.5 kN, C0 38 kN, Pu 4.8 kN, reference speed 15,000 r/min and limiting speed 18,000 r/min, mass about 220 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2304-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2304-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×21 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×21 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2304-ECP", "SKF NUP 2304 ECP" ], "locale_variants": {} }, { "sku": "NUP2305-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2305 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 62, "B_mm": 24, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 64, "static_load_kN": 55, "fatigue_load_limit_kN": 6.95, "max_rpm": 15000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 15000, "weight_g": 360, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 25 mm shaft, SKF lists NUP2305-ECP as single-row caged cylindrical roller: 62 mm OD, 24 mm wide, Pu 6.95 kN, the catalogue lists 12,000 r/min thermal reference speed and 15,000 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 25 mm seat is about 2.56 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 55 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2305-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2305, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2305 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 24 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 24 mm-wide ring and concentrates load.", "The 64/55 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2305-ECP?", "a": "SKF NUP 2305 ECP is a single-row caged cylindrical roller bearing with 25 mm bore, 62 mm OD and 24 mm width per ISO 15. SKF lists C 64 kN, C0 55 kN, Pu 6.95 kN, reference speed 12,000 r/min and limiting speed 15,000 r/min, mass about 360 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2305-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2305-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2305-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×62×24 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2305", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×62×24 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2305-ECP", "SKF NUP 2305 ECP" ], "locale_variants": {} }, { "sku": "NUP2306-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2306 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 72, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 83, "static_load_kN": 75, "fatigue_load_limit_kN": 9.65, "max_rpm": 12000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 12000, "weight_g": 540, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2306 ECP is a single-row caged cylindrical roller bearing sized 30×72×27 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 0.90 (75 against 83 kN), and the Pu figure 9.65 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 11,000 r/min thermal reference speed and 12,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 30 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2306, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2306 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 27 mm-wide ring and concentrates load.", "The 83/75 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2306-ECP?", "a": "SKF NUP 2306 ECP is a single-row caged cylindrical roller bearing with 30 mm bore, 72 mm OD and 27 mm width per ISO 15. SKF lists C 83 kN, C0 75 kN, Pu 9.65 kN, reference speed 11,000 r/min and limiting speed 12,000 r/min, mass about 540 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2306-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2306-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2306-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×72×27 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2306", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×72×27 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2306-ECP", "SKF NUP 2306 ECP" ], "locale_variants": {} }, { "sku": "NUP2307-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2307 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 80, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 106, "static_load_kN": 98, "fatigue_load_limit_kN": 12.7, "max_rpm": 11000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 11000, "weight_g": 760, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2307 ECP is a single-row caged cylindrical roller bearing sized 35×80×31 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 22.5 mm and the catalogue mass 760 g; at 106 kN dynamic rating this is roughly 3.03 kN of C per millimetre of bore before application factors. Fit practice for NUP2307-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2307, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2307 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 80 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 31 mm-wide ring and concentrates load.", "The 106/98 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2307-ECP?", "a": "SKF NUP 2307 ECP is a single-row caged cylindrical roller bearing with 35 mm bore, 80 mm OD and 31 mm width per ISO 15. SKF lists C 106 kN, C0 98 kN, Pu 12.7 kN, reference speed 9,500 r/min and limiting speed 11,000 r/min, mass about 760 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2307-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2307-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NJ2307-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×80×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2307", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×80×31 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2307-ECP", "SKF NUP 2307 ECP" ], "locale_variants": {} }, { "sku": "NUP2308-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2308 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 90, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 129, "static_load_kN": 120, "fatigue_load_limit_kN": 15.3, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 980, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2308 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 40×90×33 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 980 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 129 kN and C0 120 kN, size the bearing on the 40×90 mm ISO 15 envelope and check the 15.3 kN Pu against the equivalent-load floor; the catalogue lists 8,000 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 40 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2308, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2308 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 33 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 33 mm-wide ring and concentrates load.", "The 129/120 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2308-ECP?", "a": "SKF NUP 2308 ECP is a single-row caged cylindrical roller bearing with 40 mm bore, 90 mm OD and 33 mm width per ISO 15. SKF lists C 129 kN, C0 120 kN, Pu 15.3 kN, reference speed 8,000 r/min and limiting speed 9,500 r/min, mass about 980 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2308-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2308-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2308", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×90×33 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2308-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×90×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2308", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×90×33 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2308-ECP", "SKF NUP 2308 ECP" ], "locale_variants": {} }, { "sku": "NUP2309-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2309 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 100, "B_mm": 36, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 160, "static_load_kN": 153, "fatigue_load_limit_kN": 20, "max_rpm": 8500, "reference_speed_rpm": 7500, "limiting_speed_rpm": 8500, "weight_g": 1350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2309 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 45×100×36 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 1350 g. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP2309-ECP: the catalogue lists 7,500 r/min thermal reference speed and 8,500 r/min mechanical limiting speed. The mass entry 1350 g covers the complete catalogue execution. Fit practice for NUP2309-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2309, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2309 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 36 mm-wide ring and concentrates load.", "The 160/153 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2309-ECP?", "a": "SKF NUP 2309 ECP is a single-row caged cylindrical roller bearing with 45 mm bore, 100 mm OD and 36 mm width per ISO 15. SKF lists C 160 kN, C0 153 kN, Pu 20 kN, reference speed 7,500 r/min and limiting speed 8,500 r/min, mass about 1350 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2309-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2309-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2309", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×100×36 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2309-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×100×36 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2309", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×100×36 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2309-ECP", "SKF NUP 2309 ECP" ], "locale_variants": {} }, { "sku": "NUP2310-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2310 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 110, "B_mm": 40, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 186, "static_load_kN": 186, "fatigue_load_limit_kN": 24.5, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 1750, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2310 ECP is a single-row caged cylindrical roller bearing sized 50×110×40 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 50 mm seat is about 3.72 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 186 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 50 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2310, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2310 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 40 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 186/186 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2310-ECP?", "a": "SKF NUP 2310 ECP is a single-row caged cylindrical roller bearing with 50 mm bore, 110 mm OD and 40 mm width per ISO 15. SKF lists C 186 kN, C0 186 kN, Pu 24.5 kN, reference speed 6,700 r/min and limiting speed 8,000 r/min, mass about 1750 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2310-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2310-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2310", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×110×40 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2310-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×110×40 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2310", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×110×40 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2310-ECP", "SKF NUP 2310 ECP" ], "locale_variants": {} }, { "sku": "NUP2311-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2311 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 120, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 232, "static_load_kN": 232, "fatigue_load_limit_kN": 30.5, "max_rpm": 7000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7000, "weight_g": 2300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2311 ECP is a single-row caged cylindrical roller bearing sized 55×120×43 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 32.5 mm and the catalogue mass 2300 g; at 232 kN dynamic rating this is roughly 4.22 kN of C per millimetre of bore before application factors. Fit practice for NUP2311-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2311, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2311 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 120 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 232/232 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2311-ECP?", "a": "SKF NUP 2311 ECP is a single-row caged cylindrical roller bearing with 55 mm bore, 120 mm OD and 43 mm width per ISO 15. SKF lists C 232 kN, C0 232 kN, Pu 30.5 kN, reference speed 6,000 r/min and limiting speed 7,000 r/min, mass about 2300 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2311-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2311-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2311", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×120×43 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2311-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×120×43 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2311", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×120×43 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2311-ECP", "SKF NUP 2311 ECP" ], "locale_variants": {} }, { "sku": "NUP2312-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2312 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 130, "B_mm": 46, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 260, "static_load_kN": 265, "fatigue_load_limit_kN": 34.5, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2312 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 60×130×46 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 2850 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 260 kN and C0 265 kN, size the bearing on the 60×130 mm ISO 15 envelope and check the 34.5 kN Pu against the equivalent-load floor; the catalogue lists 5,600 r/min thermal reference speed and 6,700 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 60 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2312, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2312 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 46 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 260/265 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2312-ECP?", "a": "SKF NUP 2312 ECP is a single-row caged cylindrical roller bearing with 60 mm bore, 130 mm OD and 46 mm width per ISO 15. SKF lists C 260 kN, C0 265 kN, Pu 34.5 kN, reference speed 5,600 r/min and limiting speed 6,700 r/min, mass about 2850 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2312-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2312-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2312", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×130×46 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2312-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×130×46 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2312", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×130×46 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2312-ECP", "SKF NUP 2312 ECP" ], "locale_variants": {} }, { "sku": "NUP2313-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2313 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 140, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 285, "static_load_kN": 290, "fatigue_load_limit_kN": 38, "max_rpm": 6000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6000, "weight_g": 3450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2313 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 65×140×48 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 3450 g. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NUP2313-ECP: the catalogue lists 5,300 r/min thermal reference speed and 6,000 r/min mechanical limiting speed. The mass entry 3450 g covers the complete catalogue execution. Fit practice for NUP2313-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2313, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2313 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 285/290 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2313-ECP?", "a": "SKF NUP 2313 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 140 mm OD and 48 mm width per ISO 15. SKF lists C 285 kN, C0 290 kN, Pu 38 kN, reference speed 5,300 r/min and limiting speed 6,000 r/min, mass about 3450 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2313-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2313-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2313", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×140×48 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×48 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×48 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2313-ECP", "SKF NUP 2313 ECP" ], "locale_variants": {} }, { "sku": "NUP2314-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2314 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 150, "B_mm": 51, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 315, "static_load_kN": 325, "fatigue_load_limit_kN": 41.5, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 4150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2314 ECP resolves to a 70×150×51 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 70 mm seat is about 4.50 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 325 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2314, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2314 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 315/325 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2314-ECP?", "a": "SKF NUP 2314 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 150 mm OD and 51 mm width per ISO 15. SKF lists C 315 kN, C0 325 kN, Pu 41.5 kN, reference speed 4,800 r/min and limiting speed 5,600 r/min, mass about 4150 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2314-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2314-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2314", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×150×51 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×51 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×51 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2314-ECP", "SKF NUP 2314 ECP" ], "locale_variants": {} }, { "sku": "NUP2315-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2315 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 160, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 380, "static_load_kN": 400, "fatigue_load_limit_kN": 50, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 5100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2315-ECP is the 75 mm bore entry in the NUP2300 range: a 75×160×55 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 380 kN / C0 400 kN. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.05 (400 against 380 kN), and the Pu figure 50 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,500 r/min thermal reference speed and 5,300 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2315, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2315 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 55 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 380/400 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2315-ECP?", "a": "SKF NUP 2315 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 160 mm OD and 55 mm width per ISO 15. SKF lists C 380 kN, C0 400 kN, Pu 50 kN, reference speed 4,500 r/min and limiting speed 5,300 r/min, mass about 5100 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2315-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2315-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2315", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×160×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×55 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2315-ECP", "SKF NUP 2315 ECP" ], "locale_variants": {} }, { "sku": "NUP2316-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2316 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 170, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 415, "static_load_kN": 440, "fatigue_load_limit_kN": 55, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 6000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP2316-ECP is the 80 mm bore entry in the NUP2300 range: a 80×170×58 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 415 kN / C0 440 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 45.0 mm and the catalogue mass 6000 g; at 415 kN dynamic rating this is roughly 5.19 kN of C per millimetre of bore before application factors. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2316, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2316 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 415/440 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2316-ECP?", "a": "SKF NUP 2316 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 170 mm OD and 58 mm width per ISO 15. SKF lists C 415 kN, C0 440 kN, Pu 55 kN, reference speed 4,300 r/min and limiting speed 5,000 r/min, mass about 6000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2316-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2316-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2316", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×170×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×58 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2316-ECP", "SKF NUP 2316 ECP" ], "locale_variants": {} }, { "sku": "NUP2317-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2317 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 180, "B_mm": 60, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 455, "static_load_kN": 490, "fatigue_load_limit_kN": 60, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800, "weight_g": 7000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 85 mm shaft, SKF lists NUP2317-ECP as single-row caged cylindrical roller: 180 mm OD, 60 mm wide, Pu 60 kN, the catalogue lists 4,000 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 455 kN and C0 490 kN, size the bearing on the 85×180 mm ISO 15 envelope and check the 60 kN Pu against the equivalent-load floor; the catalogue lists 4,000 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2317, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2317 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 455/490 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2317-ECP?", "a": "SKF NUP 2317 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 180 mm OD and 60 mm width per ISO 15. SKF lists C 455 kN, C0 490 kN, Pu 60 kN, reference speed 4,000 r/min and limiting speed 4,800 r/min, mass about 7000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2317-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2317-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2317", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×180×60 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×60 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×60 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2317-ECP", "SKF NUP 2317 ECP" ], "locale_variants": {} }, { "sku": "NUP2318-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2318 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 190, "B_mm": 64, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 500, "static_load_kN": 540, "fatigue_load_limit_kN": 65.5, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 8250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 90 mm shaft, SKF lists NUP2318-ECP as single-row caged cylindrical roller: 190 mm OD, 64 mm wide, Pu 65.5 kN, the catalogue lists 3,800 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 90 mm seat is about 5.56 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 540 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2318, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2318 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 500/540 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2318-ECP?", "a": "SKF NUP 2318 ECP is a single-row caged cylindrical roller bearing with 90 mm bore, 190 mm OD and 64 mm width per ISO 15. SKF lists C 500 kN, C0 540 kN, Pu 65.5 kN, reference speed 3,800 r/min and limiting speed 4,500 r/min, mass about 8250 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2318-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2318-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2318", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×190×64 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×64 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×64 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2318-ECP", "SKF NUP 2318 ECP" ], "locale_variants": {} }, { "sku": "NUP2319-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 2319 ECJ", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 200, "B_mm": 67, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 530, "static_load_kN": 585, "fatigue_load_limit_kN": 69.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 9700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2319 ECJ resolves to a 95×200×67 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Selection arithmetic: C0/C ≈ 1.10 (585 against 530 kN), and the Pu figure 69.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,600 r/min thermal reference speed and 4,300 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2319, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2319 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 530/585 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2319-ECJ?", "a": "SKF NUP 2319 ECJ is a single-row caged cylindrical roller bearing with 95 mm bore, 200 mm OD and 67 mm width per ISO 15. SKF lists C 530 kN, C0 585 kN, Pu 69.5 kN, reference speed 3,600 r/min and limiting speed 4,300 r/min, mass about 9700 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2319-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2319-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2319", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×200×67 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2319-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×67 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2319-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×67 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2319-ECJ", "SKF NUP 2319 ECJ" ], "locale_variants": {} }, { "sku": "NUP232-ECM", "brand": "SKF", "manufacturer_designation": "SKF NUP 232 ECM", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 160, "D_mm": 290, "B_mm": 48, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 585, "static_load_kN": 680, "fatigue_load_limit_kN": 72, "max_rpm": 2600, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2600, "weight_g": 15500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 232 ECM resolves to a 160×290×48 mm single-row caged cylindrical roller bearing (dimension series 2 (light-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Speed planning for NUP232-ECM: the catalogue lists 2,400 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. The mass entry 15500 g covers the complete catalogue execution. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 160 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 232, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 232 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 48 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 585/680 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP232-ECM?", "a": "SKF NUP 232 ECM is a single-row caged cylindrical roller bearing with 160 mm bore, 290 mm OD and 48 mm width per ISO 15. SKF lists C 585 kN, C0 680 kN, Pu 72 kN, reference speed 2,400 r/min and limiting speed 2,600 r/min, mass about 15500 g." }, { "q": "What does the NUP designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP232-ECM take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP232-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP232", "equiv_brand": "NTN", "level": "partial", "note": "Same 160×290×48 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ232-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×48 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU232-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 160×290×48 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP232-ECM", "SKF NUP 232 ECM" ], "locale_variants": {} }, { "sku": "NUP2320-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 2320 ECJ", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 215, "B_mm": 73, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 670, "static_load_kN": 735, "fatigue_load_limit_kN": 85, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 12500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2320 ECJ is a single-row caged cylindrical roller bearing sized 100×215×73 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECJ: the E-design execution with a pressed sheet-steel window cage, for positions where polymer cages are temperature- or lubricant-limited. Selection arithmetic: C0/C ≈ 1.10 (735 against 670 kN), and the Pu figure 85 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 3,200 r/min thermal reference speed and 3,800 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2320, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2320 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 73 mm-wide ring and concentrates load.", "The 670/735 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2320-ECJ?", "a": "SKF NUP 2320 ECJ is a single-row caged cylindrical roller bearing with 100 mm bore, 215 mm OD and 73 mm width per ISO 15. SKF lists C 670 kN, C0 735 kN, Pu 85 kN, reference speed 3,200 r/min and limiting speed 3,800 r/min, mass about 12500 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2320-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2320-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2320", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×215×73 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2320-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×73 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2320-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×73 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2320-ECJ", "SKF NUP 2320 ECJ" ], "locale_variants": {} }, { "sku": "NUP2322-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 2322 ECP", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 240, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 780, "static_load_kN": 900, "fatigue_load_limit_kN": 102, "max_rpm": 3400, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3400, "weight_g": 17500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 2322 ECP is a single-row caged cylindrical roller bearing sized 110×240×80 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 780 kN and C0 900 kN, size the bearing on the 110×240 mm ISO 15 envelope and check the 102 kN Pu against the equivalent-load floor; the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 110 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2322, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2322 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 780/900 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2322-ECP?", "a": "SKF NUP 2322 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 240 mm OD and 80 mm width per ISO 15. SKF lists C 780 kN, C0 900 kN, Pu 102 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 17500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2322-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2322-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2322", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×240×80 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×80 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2322-ECP", "SKF NUP 2322 ECP" ], "locale_variants": {} }, { "sku": "NUP2324-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 2324 ECML", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 260, "B_mm": 86, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 915, "static_load_kN": 1040, "fatigue_load_limit_kN": 116, "max_rpm": 5000, "reference_speed_rpm": 2800, "limiting_speed_rpm": 5000, "weight_g": 23500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 2324 ECML resolves to a 120×260×86 mm single-row caged cylindrical roller bearing (dimension series 23 (medium-section, wide)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The radial section height is 70.0 mm and the catalogue mass 23500 g; at 915 kN dynamic rating this is roughly 7.63 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2324, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2324 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 915/1040 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2324-ECML?", "a": "SKF NUP 2324 ECML is a single-row caged cylindrical roller bearing with 120 mm bore, 260 mm OD and 86 mm width per ISO 15. SKF lists C 915 kN, C0 1040 kN, Pu 116 kN, reference speed 2,800 r/min and limiting speed 5,000 r/min, mass about 23500 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2324-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2324-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2324", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×260×86 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2324-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×86 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2324-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×86 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2324-ECML", "SKF NUP 2324 ECML" ], "locale_variants": {} }, { "sku": "NUP2326-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 2326 ECML", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 280, "B_mm": 93, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 1250, "fatigue_load_limit_kN": 137, "max_rpm": 4500, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4500, "weight_g": 29500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 130 mm shaft, SKF lists NUP2326-ECML as single-row caged cylindrical roller: 280 mm OD, 93 mm wide, Pu 137 kN, the catalogue lists 2,400 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. With C 1060 kN and C0 1250 kN, size the bearing on the 130×280 mm ISO 15 envelope and check the 137 kN Pu against the equivalent-load floor; the catalogue lists 2,400 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. Fit practice for NUP2326-ECML: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2326, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2326 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 93 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.", "The 1060/1250 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2326-ECML?", "a": "SKF NUP 2326 ECML is a single-row caged cylindrical roller bearing with 130 mm bore, 280 mm OD and 93 mm width per ISO 15. SKF lists C 1060 kN, C0 1250 kN, Pu 137 kN, reference speed 2,400 r/min and limiting speed 4,500 r/min, mass about 29500 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2326-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2326-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2326", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×280×93 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2326-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×93 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2326-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×93 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2326-ECML", "SKF NUP 2326 ECML" ], "locale_variants": {} }, { "sku": "NUP2328-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 2328 ECML", "series": "NUP2300-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 300, "B_mm": 102, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1200, "static_load_kN": 1430, "fatigue_load_limit_kN": 150, "max_rpm": 4300, "reference_speed_rpm": 2400, "limiting_speed_rpm": 4300, "weight_g": 37000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 2328 ECML denotes a single-row caged cylindrical roller bearing on the ISO 15 140×300×102 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 37000 g. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECML: the E-design ECML execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Load-per-bore for the 140 mm seat is about 8.57 kN/mm, typical of dimension series 23 (medium-section, wide); use C0 1430 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2328-ECML: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2328, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2328 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 300 mm raceway.", "The 1200/1430 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP2328-ECML?", "a": "SKF NUP 2328 ECML is a single-row caged cylindrical roller bearing with 140 mm bore, 300 mm OD and 102 mm width per ISO 15. SKF lists C 1200 kN, C0 1430 kN, Pu 150 kN, reference speed 2,400 r/min and limiting speed 4,300 r/min, mass about 37000 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP2328-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP2328-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP2328", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×300×102 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ2328-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×102 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU2328-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×102 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP2328-ECML", "SKF NUP 2328 ECML" ], "locale_variants": {} }, { "sku": "NUP238-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 238 ECML", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 190, "D_mm": 340, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 800, "static_load_kN": 965, "fatigue_load_limit_kN": 98, "max_rpm": 3400, "reference_speed_rpm": 2000, "limiting_speed_rpm": 3400, "weight_g": 22500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 190 mm shaft, SKF lists NUP238-ECML as single-row caged cylindrical roller: 340 mm OD, 55 mm wide, Pu 98 kN, the catalogue lists 2,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 190 mm seat is about 4.21 kN/mm, typical of dimension series 2 (light-section ISO 15 envelope); use C0 965 kN for static checks such as crane hook blocks standing under load. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 238, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 238 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 800/965 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP238-ECML?", "a": "SKF NUP 238 ECML is a single-row caged cylindrical roller bearing with 190 mm bore, 340 mm OD and 55 mm width per ISO 15. SKF lists C 800 kN, C0 965 kN, Pu 98 kN, reference speed 2,000 r/min and limiting speed 3,400 r/min, mass about 22500 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP238-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP238-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP238", "equiv_brand": "NTN", "level": "partial", "note": "Same 190×340×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ238-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU238-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 190×340×55 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP238-ECML", "SKF NUP 238 ECML" ], "locale_variants": {} }, { "sku": "NUP244-ECML", "brand": "SKF", "manufacturer_designation": "SKF NUP 244 ECML", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 220, "D_mm": 400, "B_mm": 65, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1060, "static_load_kN": 1290, "fatigue_load_limit_kN": 125, "max_rpm": 3000, "reference_speed_rpm": 1700, "limiting_speed_rpm": 3000, "weight_g": 37500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP244-ECML is the 220 mm bore entry in the NUP200 range: a 220×400×65 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1060 kN / C0 1290 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Speed planning for NUP244-ECML: the catalogue lists 1,700 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 37500 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 244, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 244 ECML and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 400 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 1060/1290 kN ratings are SKF catalogue 17000 (2018) values for the ECML execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP244-ECML?", "a": "SKF NUP 244 ECML is a single-row caged cylindrical roller bearing with 220 mm bore, 400 mm OD and 65 mm width per ISO 15. SKF lists C 1060 kN, C0 1290 kN, Pu 125 kN, reference speed 1,700 r/min and limiting speed 3,000 r/min, mass about 37500 g." }, { "q": "What does the NUP designation and ECML suffix mean?", "a": "The ECML suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP244-ECML take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP244-ECML compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP244", "equiv_brand": "NTN", "level": "partial", "note": "Same 220×400×65 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ244-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×65 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU244-ECML", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 220×400×65 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP244-ECML", "SKF NUP 244 ECML" ], "locale_variants": {} }, { "sku": "NUP248-MA", "brand": "SKF", "manufacturer_designation": "SKF NUP 248 MA", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 240, "D_mm": 440, "B_mm": 72, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 952, "static_load_kN": 1370, "fatigue_load_limit_kN": 129, "max_rpm": 2200, "reference_speed_rpm": 1600, "limiting_speed_rpm": 2200, "weight_g": 53000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP248-MA is the 240 mm bore entry in the NUP200 range: a 240×440×72 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 952 kN / C0 1370 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix MA: the basic (non-E) MA execution with a machined brass cage, standard for the larger and earlier-design sizes. The radial section height is 100.0 mm and the catalogue mass 53000 g; at 952 kN dynamic rating this is roughly 3.97 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 248, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 248 MA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 440 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 72 mm-wide ring and concentrates load.", "The 952/1370 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP248-MA?", "a": "SKF NUP 248 MA is a single-row caged cylindrical roller bearing with 240 mm bore, 440 mm OD and 72 mm width per ISO 15. SKF lists C 952 kN, C0 1370 kN, Pu 129 kN, reference speed 1,600 r/min and limiting speed 2,200 r/min, mass about 53000 g." }, { "q": "What does the NUP designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP248-MA take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP248-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP248", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ248-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×440×72 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU248-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 240×440×72 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP248-MA", "SKF NUP 248 MA" ], "locale_variants": {} }, { "sku": "NUP252-MA", "brand": "SKF", "manufacturer_designation": "SKF NUP 252 MA", "series": "NUP200-series", "type": "cylindrical_roller", "d_mm": 260, "D_mm": 480, "B_mm": 80, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1170, "static_load_kN": 1700, "fatigue_load_limit_kN": 150, "max_rpm": 2000, "reference_speed_rpm": 1400, "limiting_speed_rpm": 2000, "weight_g": 72000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP252-MA is the 260 mm bore entry in the NUP200 range: a 260×480×80 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 1170 kN / C0 1700 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Speed planning for NUP252-MA: the catalogue lists 1,400 r/min thermal reference speed and 2,000 r/min mechanical limiting speed. The mass entry 72000 g covers the complete catalogue execution. Fit practice for NUP252-MA: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 2 (light-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 252, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 252 MA and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 80 mm-wide ring and concentrates load.", "The 1170/1700 kN ratings are SKF catalogue 17000 (2018) values for the MA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP252-MA?", "a": "SKF NUP 252 MA is a single-row caged cylindrical roller bearing with 260 mm bore, 480 mm OD and 80 mm width per ISO 15. SKF lists C 1170 kN, C0 1700 kN, Pu 150 kN, reference speed 1,400 r/min and limiting speed 2,000 r/min, mass about 72000 g." }, { "q": "What does the NUP designation and MA suffix mean?", "a": "The MA suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP252-MA take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP252-MA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP252", "equiv_brand": "NTN", "level": "full", "note": "Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier." }, { "equiv_sku": "NJ252-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×480×80 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU252-MA", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 260×480×80 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP252-MA", "SKF NUP 252 MA" ], "locale_variants": {} }, { "sku": "NUP29-530-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NUP 29/530 ECMA", "series": "NUP2900-series", "type": "cylindrical_roller", "d_mm": 530, "D_mm": 710, "B_mm": 106, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2380, "static_load_kN": 5000, "fatigue_load_limit_kN": 390, "max_rpm": 1100, "reference_speed_rpm": 850, "limiting_speed_rpm": 1100, "weight_g": 130000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 29/530 ECMA resolves to a 530×710×106 mm single-row caged cylindrical roller bearing (dimension series 29 (compact OD, normal width)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. With C 2380 kN and C0 5000 kN, size the bearing on the 530×710 mm ISO 15 envelope and check the 390 kN Pu against the equivalent-load floor; the catalogue lists 850 r/min thermal reference speed and 1,100 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "heavy turbogenerator rotor supports", "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 29 (compact OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 29/530, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 29/530 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 710 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 710 mm raceway.", "The 2380/5000 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP29-530-ECMA?", "a": "SKF NUP 29/530 ECMA is a single-row caged cylindrical roller bearing with 530 mm bore, 710 mm OD and 106 mm width per ISO 15. SKF lists C 2380 kN, C0 5000 kN, Pu 390 kN, reference speed 850 r/min and limiting speed 1,100 r/min, mass about 130000 g." }, { "q": "What does the NUP designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP29-530-ECMA take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP29-530-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP29", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP29-530-ECMA", "SKF NUP 29/530 ECMA" ], "locale_variants": {} }, { "sku": "NUP304-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 304 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 20, "D_mm": 52, "B_mm": 15, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 35.5, "static_load_kN": 26, "fatigue_load_limit_kN": 3.25, "max_rpm": 18000, "reference_speed_rpm": 15000, "limiting_speed_rpm": 18000, "weight_g": 160, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 304 ECP is a single-row caged cylindrical roller bearing sized 20×52×15 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 20 mm seat is about 1.77 kN/mm, typical of dimension series 3 (medium-section ISO 15 envelope); use C0 26 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 20 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.", "applications": [ "small pump rotor shafts", "small industrial electric-motor shafts", "light gearbox layshafts", "motor-cycle and small-engine transmissions" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 304, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 304 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 15 mm-wide ring and concentrates load.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 15 mm-wide ring and concentrates load.", "The 35.5/26 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP304-ECP?", "a": "SKF NUP 304 ECP is a single-row caged cylindrical roller bearing with 20 mm bore, 52 mm OD and 15 mm width per ISO 15. SKF lists C 35.5 kN, C0 26 kN, Pu 3.25 kN, reference speed 15,000 r/min and limiting speed 18,000 r/min, mass about 160 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP304-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP304-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×15 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ304-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×15 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU304", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 20×52×15 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP304-ECP", "SKF NUP 304 ECP" ], "locale_variants": {} }, { "sku": "NUP305-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 305 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 25, "D_mm": 62, "B_mm": 17, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 46.5, "static_load_kN": 36.5, "fatigue_load_limit_kN": 4.55, "max_rpm": 15000, "reference_speed_rpm": 12000, "limiting_speed_rpm": 15000, "weight_g": 250, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 305 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 25×62×17 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 250 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 18.5 mm and the catalogue mass 250 g; at 46.5 kN dynamic rating this is roughly 1.86 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "light gearbox layshafts", "motor-cycle and small-engine transmissions", "appliance and fan armature shafts", "small pump rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 305, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 305 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 62 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 17 mm-wide ring and concentrates load.", "The 46.5/36.5 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP305-ECP?", "a": "SKF NUP 305 ECP is a single-row caged cylindrical roller bearing with 25 mm bore, 62 mm OD and 17 mm width per ISO 15. SKF lists C 46.5 kN, C0 36.5 kN, Pu 4.55 kN, reference speed 12,000 r/min and limiting speed 15,000 r/min, mass about 250 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP305-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP305-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N305-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×62×17 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ305-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×62×17 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU305", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 25×62×17 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP305-ECP", "SKF NUP 305 ECP" ], "locale_variants": {} }, { "sku": "NUP306-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 306 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 30, "D_mm": 72, "B_mm": 19, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 58.5, "static_load_kN": 48, "fatigue_load_limit_kN": 6.2, "max_rpm": 12000, "reference_speed_rpm": 11000, "limiting_speed_rpm": 12000, "weight_g": 380, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 306 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 30×72×19 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 380 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 21.0 mm and the catalogue mass 380 g; at 58.5 kN dynamic rating this is roughly 1.95 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 306, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 306 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 19 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 58.5/48 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP306-ECP?", "a": "SKF NUP 306 ECP is a single-row caged cylindrical roller bearing with 30 mm bore, 72 mm OD and 19 mm width per ISO 15. SKF lists C 58.5 kN, C0 48 kN, Pu 6.2 kN, reference speed 11,000 r/min and limiting speed 12,000 r/min, mass about 380 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP306-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP306-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N306-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×72×19 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ306-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×72×19 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU306", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 30×72×19 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP306-ECP", "SKF NUP 306 ECP" ], "locale_variants": {} }, { "sku": "NUP307-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 307 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 35, "D_mm": 80, "B_mm": 21, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 75, "static_load_kN": 63, "fatigue_load_limit_kN": 8.15, "max_rpm": 11000, "reference_speed_rpm": 9500, "limiting_speed_rpm": 11000, "weight_g": 490, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 307 ECP resolves to a 35×80×21 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. With C 75 kN and C0 63 kN, size the bearing on the 35×80 mm ISO 15 envelope and check the 8.15 kN Pu against the equivalent-load floor; the catalogue lists 9,500 r/min thermal reference speed and 11,000 r/min mechanical limiting speed. Fit practice for NUP307-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 307, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 307 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 75/63 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP307-ECP?", "a": "SKF NUP 307 ECP is a single-row caged cylindrical roller bearing with 35 mm bore, 80 mm OD and 21 mm width per ISO 15. SKF lists C 75 kN, C0 63 kN, Pu 8.15 kN, reference speed 9,500 r/min and limiting speed 11,000 r/min, mass about 490 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP307-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP307-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "N307-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×80×21 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ307-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×80×21 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU307", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 35×80×21 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP307-ECP", "SKF NUP 307 ECP" ], "locale_variants": {} }, { "sku": "NUP308-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 308 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 40, "D_mm": 90, "B_mm": 23, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 93, "static_load_kN": 78, "fatigue_load_limit_kN": 10.2, "max_rpm": 9500, "reference_speed_rpm": 8000, "limiting_speed_rpm": 9500, "weight_g": 680, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 308 ECP resolves to a 40×90×23 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP308-ECP: the catalogue lists 8,000 r/min thermal reference speed and 9,500 r/min mechanical limiting speed. The mass entry 680 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "machine-tool radial spindle supports", "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 308, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 308 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 90 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 93/78 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP308-ECP?", "a": "SKF NUP 308 ECP is a single-row caged cylindrical roller bearing with 40 mm bore, 90 mm OD and 23 mm width per ISO 15. SKF lists C 93 kN, C0 78 kN, Pu 10.2 kN, reference speed 8,000 r/min and limiting speed 9,500 r/min, mass about 680 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP308-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP308-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP308", "equiv_brand": "NTN", "level": "partial", "note": "Same 40×90×23 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N308-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×90×23 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ308-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×90×23 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU308", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 40×90×23 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP308-ECP", "SKF NUP 308 ECP" ], "locale_variants": {} }, { "sku": "NUP309-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 309 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 45, "D_mm": 100, "B_mm": 25, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 112, "static_load_kN": 100, "fatigue_load_limit_kN": 12.9, "max_rpm": 8500, "reference_speed_rpm": 7500, "limiting_speed_rpm": 8500, "weight_g": 930, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP309-ECP is the 45 mm bore entry in the NUP300 range: a 45×100×25 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 112 kN / C0 100 kN. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Load-per-bore for the 45 mm seat is about 2.49 kN/mm, typical of dimension series 3 (medium-section ISO 15 envelope); use C0 100 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP309-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "conveyor drive-pulley shafts", "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 309, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 309 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 25 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 112/100 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP309-ECP?", "a": "SKF NUP 309 ECP is a single-row caged cylindrical roller bearing with 45 mm bore, 100 mm OD and 25 mm width per ISO 15. SKF lists C 112 kN, C0 100 kN, Pu 12.9 kN, reference speed 7,500 r/min and limiting speed 8,500 r/min, mass about 930 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP309-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP309-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP309", "equiv_brand": "NTN", "level": "partial", "note": "Same 45×100×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N309-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×100×25 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ309-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×100×25 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU309", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 45×100×25 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP309-ECP", "SKF NUP 309 ECP" ], "locale_variants": {} }, { "sku": "NUP310-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 310 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 50, "D_mm": 110, "B_mm": 27, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 127, "static_load_kN": 112, "fatigue_load_limit_kN": 15, "max_rpm": 8000, "reference_speed_rpm": 6700, "limiting_speed_rpm": 8000, "weight_g": 1150, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 310 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 50×110×27 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 1150 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 0.88 (112 against 127 kN), and the Pu figure 15 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 6,700 r/min thermal reference speed and 8,000 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "medium industrial gearbox shafts", "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "false brinelling on standby machines exposed to external vibration" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 310, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 310 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 110 mm raceway.", "The 127/112 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP310-ECP?", "a": "SKF NUP 310 ECP is a single-row caged cylindrical roller bearing with 50 mm bore, 110 mm OD and 27 mm width per ISO 15. SKF lists C 127 kN, C0 112 kN, Pu 15 kN, reference speed 6,700 r/min and limiting speed 8,000 r/min, mass about 1150 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP310-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP310-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP310", "equiv_brand": "NTN", "level": "partial", "note": "Same 50×110×27 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N310-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×110×27 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ310-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×110×27 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU310", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 50×110×27 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP310-ECP", "SKF NUP 310 ECP" ], "locale_variants": {} }, { "sku": "NUP311-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 311 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 55, "D_mm": 120, "B_mm": 29, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 156, "static_load_kN": 143, "fatigue_load_limit_kN": 18.6, "max_rpm": 7000, "reference_speed_rpm": 6000, "limiting_speed_rpm": 7000, "weight_g": 1500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 311 ECP resolves to a 55×120×29 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 32.5 mm and the catalogue mass 1500 g; at 156 kN dynamic rating this is roughly 2.84 kN of C per millimetre of bore before application factors. Fit practice for NUP311-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "electric-motor shafts in pumps and fans", "compressor crank and rotor shafts", "machine-tool radial spindle supports", "conveyor drive-pulley shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 311, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 311 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 29 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 120 mm raceway.", "The 156/143 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP311-ECP?", "a": "SKF NUP 311 ECP is a single-row caged cylindrical roller bearing with 55 mm bore, 120 mm OD and 29 mm width per ISO 15. SKF lists C 156 kN, C0 143 kN, Pu 18.6 kN, reference speed 6,000 r/min and limiting speed 7,000 r/min, mass about 1500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP311-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP311-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP311", "equiv_brand": "NTN", "level": "partial", "note": "Same 55×120×29 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N311-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×120×29 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ311-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×120×29 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU311", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 55×120×29 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP311-ECP", "SKF NUP 311 ECP" ], "locale_variants": {} }, { "sku": "NUP312-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 312 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 60, "D_mm": 130, "B_mm": 31, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 173, "static_load_kN": 160, "fatigue_load_limit_kN": 21.2, "max_rpm": 6700, "reference_speed_rpm": 5600, "limiting_speed_rpm": 6700, "weight_g": 1900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 312 ECP resolves to a 60×130×31 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Speed planning for NUP312-ECP: the catalogue lists 5,600 r/min thermal reference speed and 6,700 r/min mechanical limiting speed. The mass entry 1900 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 312, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 312 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 130 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 130 mm raceway.", "The 173/160 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP312-ECP?", "a": "SKF NUP 312 ECP is a single-row caged cylindrical roller bearing with 60 mm bore, 130 mm OD and 31 mm width per ISO 15. SKF lists C 173 kN, C0 160 kN, Pu 21.2 kN, reference speed 5,600 r/min and limiting speed 6,700 r/min, mass about 1900 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP312-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP312-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP312", "equiv_brand": "NTN", "level": "partial", "note": "Same 60×130×31 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N312-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×130×31 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ312-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×130×31 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU312", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 60×130×31 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP312-ECP", "SKF NUP 312 ECP" ], "locale_variants": {} }, { "sku": "NUP313-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 313 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 65, "D_mm": 140, "B_mm": 33, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 212, "static_load_kN": 196, "fatigue_load_limit_kN": 25.5, "max_rpm": 6000, "reference_speed_rpm": 5300, "limiting_speed_rpm": 6000, "weight_g": 2350, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP313-ECP is the 65 mm bore entry in the NUP300 range: a 65×140×33 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 212 kN / C0 196 kN. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Load-per-bore for the 65 mm seat is about 3.26 kN/mm, typical of dimension series 3 (medium-section ISO 15 envelope); use C0 196 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP313-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 313, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 313 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 33 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 140 mm raceway.", "The 212/196 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP313-ECP?", "a": "SKF NUP 313 ECP is a single-row caged cylindrical roller bearing with 65 mm bore, 140 mm OD and 33 mm width per ISO 15. SKF lists C 212 kN, C0 196 kN, Pu 25.5 kN, reference speed 5,300 r/min and limiting speed 6,000 r/min, mass about 2350 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP313-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP313-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP313", "equiv_brand": "NTN", "level": "partial", "note": "Same 65×140×33 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×33 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ313-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×33 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU313", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 65×140×33 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP313-ECP", "SKF NUP 313 ECP" ], "locale_variants": {} }, { "sku": "NUP314-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 314 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 70, "D_mm": 150, "B_mm": 35, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 236, "static_load_kN": 228, "fatigue_load_limit_kN": 29, "max_rpm": 5600, "reference_speed_rpm": 4800, "limiting_speed_rpm": 5600, "weight_g": 2850, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 70 mm shaft, SKF lists NUP314-ECP as single-row caged cylindrical roller: 150 mm OD, 35 mm wide, Pu 29 kN, the catalogue lists 4,800 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 0.97 (228 against 236 kN), and the Pu figure 29 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 4,800 r/min thermal reference speed and 5,600 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 70 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 314, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 314 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 150 mm raceway.", "The 236/228 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP314-ECP?", "a": "SKF NUP 314 ECP is a single-row caged cylindrical roller bearing with 70 mm bore, 150 mm OD and 35 mm width per ISO 15. SKF lists C 236 kN, C0 228 kN, Pu 29 kN, reference speed 4,800 r/min and limiting speed 5,600 r/min, mass about 2850 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP314-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP314-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP314", "equiv_brand": "NTN", "level": "partial", "note": "Same 70×150×35 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×35 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ314-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×35 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU314", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 70×150×35 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP314-ECP", "SKF NUP 314 ECP" ], "locale_variants": {} }, { "sku": "NUP315-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 315 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 75, "D_mm": 160, "B_mm": 37, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 280, "static_load_kN": 265, "fatigue_load_limit_kN": 33.5, "max_rpm": 5300, "reference_speed_rpm": 4500, "limiting_speed_rpm": 5300, "weight_g": 3450, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 75 mm shaft, SKF lists NUP315-ECP as single-row caged cylindrical roller: 160 mm OD, 37 mm wide, Pu 33.5 kN, the catalogue lists 4,500 r/min thermal reference speed and 5,300 r/min mechanical limiting speed. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The radial section height is 42.5 mm and the catalogue mass 3450 g; at 280 kN dynamic rating this is roughly 3.73 kN of C per millimetre of bore before application factors. Fit practice for NUP315-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 315, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 315 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 160 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 160 mm raceway.", "The 280/265 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP315-ECP?", "a": "SKF NUP 315 ECP is a single-row caged cylindrical roller bearing with 75 mm bore, 160 mm OD and 37 mm width per ISO 15. SKF lists C 280 kN, C0 265 kN, Pu 33.5 kN, reference speed 4,500 r/min and limiting speed 5,300 r/min, mass about 3450 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP315-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP315-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP315", "equiv_brand": "NTN", "level": "partial", "note": "Same 75×160×37 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×37 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ315-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×37 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU315", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 75×160×37 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP315-ECP", "SKF NUP 315 ECP" ], "locale_variants": {} }, { "sku": "NUP316-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 316 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 80, "D_mm": 170, "B_mm": 39, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 300, "static_load_kN": 290, "fatigue_load_limit_kN": 36, "max_rpm": 5000, "reference_speed_rpm": 4300, "limiting_speed_rpm": 5000, "weight_g": 4100, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 316 ECP is a single-row caged cylindrical roller bearing sized 80×170×39 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. With C 300 kN and C0 290 kN, size the bearing on the 80×170 mm ISO 15 envelope and check the 36 kN Pu against the equivalent-load floor; the catalogue lists 4,300 r/min thermal reference speed and 5,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 80 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "hard-particle indentation of the raceway in unfiltered oil systems" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 316, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 316 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 39 mm-wide ring and concentrates load.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 170 mm raceway.", "The 300/290 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP316-ECP?", "a": "SKF NUP 316 ECP is a single-row caged cylindrical roller bearing with 80 mm bore, 170 mm OD and 39 mm width per ISO 15. SKF lists C 300 kN, C0 290 kN, Pu 36 kN, reference speed 4,300 r/min and limiting speed 5,000 r/min, mass about 4100 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP316-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP316-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP316", "equiv_brand": "NTN", "level": "partial", "note": "Same 80×170×39 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×39 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ316-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×39 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU316", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 80×170×39 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP316-ECP", "SKF NUP 316 ECP" ], "locale_variants": {} }, { "sku": "NUP317-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 317 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 85, "D_mm": 180, "B_mm": 41, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 340, "static_load_kN": 335, "fatigue_load_limit_kN": 41.5, "max_rpm": 4800, "reference_speed_rpm": 4000, "limiting_speed_rpm": 4800, "weight_g": 4900, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 317 ECP is a single-row caged cylindrical roller bearing sized 85×180×41 mm — a dimension series 3 (medium-section ISO 15 envelope), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECP: the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP317-ECP: the catalogue lists 4,000 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. The mass entry 4900 g covers the complete catalogue execution. Fit practice for NUP317-ECP: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "electrical pitting on VFD-driven shafts without grounding protection" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 317, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 317 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 180 mm raceway.", "The 340/335 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP317-ECP?", "a": "SKF NUP 317 ECP is a single-row caged cylindrical roller bearing with 85 mm bore, 180 mm OD and 41 mm width per ISO 15. SKF lists C 340 kN, C0 335 kN, Pu 41.5 kN, reference speed 4,000 r/min and limiting speed 4,800 r/min, mass about 4900 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP317-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP317-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP317", "equiv_brand": "NTN", "level": "partial", "note": "Same 85×180×41 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×41 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ317-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×41 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU317", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 85×180×41 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP317-ECP", "SKF NUP 317 ECP" ], "locale_variants": {} }, { "sku": "NUP318-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 318 ECJ", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 90, "D_mm": 190, "B_mm": 43, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 365, "static_load_kN": 360, "fatigue_load_limit_kN": 43, "max_rpm": 4500, "reference_speed_rpm": 3800, "limiting_speed_rpm": 4500, "weight_g": 5550, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP318-ECJ is the 90 mm bore entry in the NUP300 range: a 90×190×43 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 365 kN / C0 360 kN. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Load-per-bore for the 90 mm seat is about 4.06 kN/mm, typical of dimension series 3 (medium-section ISO 15 envelope); use C0 360 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 90 mm seat normally takes a k5 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors", "rolling-mill auxiliary drive shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 318, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 318 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 190 mm raceway.", "The 365/360 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP318-ECJ?", "a": "SKF NUP 318 ECJ is a single-row caged cylindrical roller bearing with 90 mm bore, 190 mm OD and 43 mm width per ISO 15. SKF lists C 365 kN, C0 360 kN, Pu 43 kN, reference speed 3,800 r/min and limiting speed 4,500 r/min, mass about 5550 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP318-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP318-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP318", "equiv_brand": "NTN", "level": "partial", "note": "Same 90×190×43 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×43 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ318-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×43 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU318", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 90×190×43 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP318-ECJ", "SKF NUP 318 ECJ" ], "locale_variants": {} }, { "sku": "NUP319-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 319 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 95, "D_mm": 200, "B_mm": 45, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 390, "static_load_kN": 390, "fatigue_load_limit_kN": 46.5, "max_rpm": 4300, "reference_speed_rpm": 3600, "limiting_speed_rpm": 4300, "weight_g": 6300, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 319 ECP resolves to a 95×200×45 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. The radial section height is 52.5 mm and the catalogue mass 6300 g; at 390 kN dynamic rating this is roughly 4.11 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 319, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 319 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 200 mm raceway.", "The 390/390 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP319-ECP?", "a": "SKF NUP 319 ECP is a single-row caged cylindrical roller bearing with 95 mm bore, 200 mm OD and 45 mm width per ISO 15. SKF lists C 390 kN, C0 390 kN, Pu 46.5 kN, reference speed 3,600 r/min and limiting speed 4,300 r/min, mass about 6300 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP319-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP319-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP319", "equiv_brand": "NTN", "level": "partial", "note": "Same 95×200×45 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N319-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×45 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ319-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×45 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU319", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 95×200×45 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP319-ECP", "SKF NUP 319 ECP" ], "locale_variants": {} }, { "sku": "NUP320-ECJ", "brand": "SKF", "manufacturer_designation": "SKF NUP 320 ECJ", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 100, "D_mm": 215, "B_mm": 47, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "steel_stamped_J", "dynamic_load_kN": 450, "static_load_kN": 440, "fatigue_load_limit_kN": 51, "max_rpm": 3800, "reference_speed_rpm": 3200, "limiting_speed_rpm": 3800, "weight_g": 7700, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 320 ECJ resolves to a 100×215×47 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. The radial section height is 57.5 mm and the catalogue mass 7700 g; at 450 kN dynamic rating this is roughly 4.50 kN of C per millimetre of bore before application factors. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "large pump and blower rotors", "rolling-mill auxiliary drive shafts", "paper-machine press rolls", "cement-plant conveyor drives" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 320, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 320 ECJ and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 47 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 450/440 kN ratings are SKF catalogue 17000 (2018) values for the ECJ execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP320-ECJ?", "a": "SKF NUP 320 ECJ is a single-row caged cylindrical roller bearing with 100 mm bore, 215 mm OD and 47 mm width per ISO 15. SKF lists C 450 kN, C0 440 kN, Pu 51 kN, reference speed 3,200 r/min and limiting speed 3,800 r/min, mass about 7700 g." }, { "q": "What does the NUP designation and ECJ suffix mean?", "a": "The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP320-ECJ take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP320-ECJ compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP320", "equiv_brand": "NTN", "level": "partial", "note": "Same 100×215×47 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N320-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×47 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ320-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×47 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU320", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 100×215×47 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP320-ECJ", "SKF NUP 320 ECJ" ], "locale_variants": {} }, { "sku": "NUP322-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 322 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 110, "D_mm": 240, "B_mm": 50, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 530, "static_load_kN": 540, "fatigue_load_limit_kN": 61, "max_rpm": 3400, "reference_speed_rpm": 3000, "limiting_speed_rpm": 3400, "weight_g": 10500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 322 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 110×240×50 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 10500 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP322-ECP: the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 10500 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "paper-machine press rolls", "cement-plant conveyor drives", "heavy gearbox and pinion shafts", "large pump and blower rotors" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 322, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 322 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 240 mm raceway.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 530/540 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP322-ECP?", "a": "SKF NUP 322 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 530 kN, C0 540 kN, Pu 61 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 10500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP322-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP322-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP322", "equiv_brand": "NTN", "level": "partial", "note": "Same 110×240×50 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ322-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU322-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP322-ECP", "SKF NUP 322 ECP" ], "locale_variants": {} }, { "sku": "NUP324-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 324 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 120, "D_mm": 260, "B_mm": 55, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 610, "static_load_kN": 620, "fatigue_load_limit_kN": 69.5, "max_rpm": 3200, "reference_speed_rpm": 2800, "limiting_speed_rpm": 3200, "weight_g": 14000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "Ordering number SKF NUP 324 ECP resolves to a 120×260×55 mm single-row caged cylindrical roller bearing (dimension series 3 (medium-section ISO 15 envelope)); two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Selection arithmetic: C0/C ≈ 1.02 (620 against 610 kN), and the Pu figure 69.5 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,800 r/min thermal reference speed and 3,200 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 324, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 324 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 610/620 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP324-ECP?", "a": "SKF NUP 324 ECP is a single-row caged cylindrical roller bearing with 120 mm bore, 260 mm OD and 55 mm width per ISO 15. SKF lists C 610 kN, C0 620 kN, Pu 69.5 kN, reference speed 2,800 r/min and limiting speed 3,200 r/min, mass about 14000 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP324-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP324-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP324", "equiv_brand": "NTN", "level": "partial", "note": "Same 120×260×55 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N324-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ324-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU324-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 120×260×55 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP324-ECP", "SKF NUP 324 ECP" ], "locale_variants": {} }, { "sku": "NUP326-ECP", "brand": "SKF", "manufacturer_designation": "SKF NUP 326 ECP", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 130, "D_mm": 280, "B_mm": 58, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "polymer_PA66", "dynamic_load_kN": 720, "static_load_kN": 750, "fatigue_load_limit_kN": 81.5, "max_rpm": 3000, "reference_speed_rpm": 2400, "limiting_speed_rpm": 3000, "weight_g": 19500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "NUP326-ECP is the 130 mm bore entry in the NUP300 range: a 130×280×58 mm single-row caged cylindrical roller bearing with a glass-fibre reinforced polyamide (PA66) window-type cage, rated C 720 kN / C0 750 kN. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP326-ECP: the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 19500 g covers the complete catalogue execution. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.", "applications": [ "mining hoist and winder shafts", "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "polymer cage softening above 120 °C", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "fretting corrosion on a loose rotating shaft seat or in a vibratory stand-still" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 326, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 326 ECP and do not substitute rib styles without checking the shaft locating scheme.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 720/750 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP326-ECP?", "a": "SKF NUP 326 ECP is a single-row caged cylindrical roller bearing with 130 mm bore, 280 mm OD and 58 mm width per ISO 15. SKF lists C 720 kN, C0 750 kN, Pu 81.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 19500 g." }, { "q": "What does the NUP designation and ECP suffix mean?", "a": "The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP326-ECP take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP326-ECP compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP326", "equiv_brand": "NTN", "level": "partial", "note": "Same 130×280×58 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "N326-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NJ326-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU326-ECP", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP326-ECP", "SKF NUP 326 ECP" ], "locale_variants": {} }, { "sku": "NUP328-ECM", "brand": "SKF", "manufacturer_designation": "SKF NUP 328 ECM", "series": "NUP300-series", "type": "cylindrical_roller", "d_mm": 140, "D_mm": 300, "B_mm": 62, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 780, "static_load_kN": 830, "fatigue_load_limit_kN": 88, "max_rpm": 2800, "reference_speed_rpm": 2400, "limiting_speed_rpm": 2800, "weight_g": 23500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "In SKF catalogue PUB BU/P1 17000, SKF NUP 328 ECM denotes a single-row caged cylindrical roller bearing on the ISO 15 140×300×62 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 23500 g. Reading the NUP prefix: two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. This makes the execution a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECM: the E-design ECM execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 1.06 (830 against 780 kN), and the Pu figure 88 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,400 r/min thermal reference speed and 2,800 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 140 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 328, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 328 ECM and do not substitute rib styles without checking the shaft locating scheme.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 62 mm-wide ring and concentrates load.", "Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.", "The 780/830 kN ratings are SKF catalogue 17000 (2018) values for the ECM execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP328-ECM?", "a": "SKF NUP 328 ECM is a single-row caged cylindrical roller bearing with 140 mm bore, 300 mm OD and 62 mm width per ISO 15. SKF lists C 780 kN, C0 830 kN, Pu 88 kN, reference speed 2,400 r/min and limiting speed 2,800 r/min, mass about 23500 g." }, { "q": "What does the NUP designation and ECM suffix mean?", "a": "The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP328-ECM take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP328-ECM compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP328", "equiv_brand": "NTN", "level": "partial", "note": "Same 140×300×62 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting." }, { "equiv_sku": "NJ328-ECJ", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." }, { "equiv_sku": "NU328-ECM", "equiv_brand": "SKF", "level": "full", "note": "Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical." } ], "source_ref": "https://www.skf.com/group/products/rolling-bearings/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP328-ECM", "SKF NUP 328 ECM" ], "locale_variants": {} }, { "sku": "NUP3984-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NUP 3984 ECMA", "series": "NUP3900-series", "type": "cylindrical_roller", "d_mm": 420, "D_mm": 560, "B_mm": 106, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 1680, "static_load_kN": 3650, "fatigue_load_limit_kN": 310, "max_rpm": 1500, "reference_speed_rpm": 950, "limiting_speed_rpm": 1500, "weight_g": 79500, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "For a 420 mm shaft, SKF lists NUP3984-ECMA as single-row caged cylindrical roller: 560 mm OD, 106 mm wide, Pu 310 kN, the catalogue lists 950 r/min thermal reference speed and 1,500 r/min mechanical limiting speed. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Load-per-bore for the 420 mm seat is about 4.00 kN/mm, typical of dimension series 39 (compact OD); use C0 3650 kN for static checks such as crane hook blocks standing under load. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 420 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.", "applications": [ "offshore drawworks shafts", "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "rolling-contact fatigue spalling after the rated L10 life is exceeded" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 39 (compact OD) envelope is shared with the N/NU/NJ/NUP executions of 3984, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 3984 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 560 mm raceway.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 560 mm raceway.", "The 1680/3650 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP3984-ECMA?", "a": "SKF NUP 3984 ECMA is a single-row caged cylindrical roller bearing with 420 mm bore, 560 mm OD and 106 mm width per ISO 15. SKF lists C 1680 kN, C0 3650 kN, Pu 310 kN, reference speed 950 r/min and limiting speed 1,500 r/min, mass about 79500 g." }, { "q": "What does the NUP designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP3984-ECMA take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP3984-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP3984", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP3984-ECMA", "SKF NUP 3984 ECMA" ], "locale_variants": {} }, { "sku": "NUP3992-ECMA", "brand": "SKF", "manufacturer_designation": "SKF NUP 3992 ECMA", "series": "NUP3900-series", "type": "cylindrical_roller", "d_mm": 460, "D_mm": 620, "B_mm": 118, "material": "GCr15", "seal_type": "open", "clearance": "CN", "tolerance_class": "P0", "cage_type": "brass", "dynamic_load_kN": 2050, "static_load_kN": 4550, "fatigue_load_limit_kN": 375, "max_rpm": 1300, "reference_speed_rpm": 850, "limiting_speed_rpm": 1300, "weight_g": 112000, "weight_estimated": false, "temp_min_c": -40, "temp_max_c": 120, "standard": "ISO 15", "naming_rule_text": "SKF NUP 3992 ECMA is a single-row caged cylindrical roller bearing sized 460×620×118 mm — a dimension series 39 (compact OD), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. Reading the order-string suffix ECMA: the E-design ECMA execution with a one-piece machined brass cage for higher-temperature, higher-speed continuous duty. Selection arithmetic: C0/C ≈ 2.22 (4550 against 2050 kN), and the Pu figure 375 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 850 r/min thermal reference speed and 1,300 r/min mechanical limiting speed. Assembly note: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Heat steel rings inductively to max 120 °C.", "applications": [ "large rolling-mill drive trains", "marine propulsion line shafts", "heavy turbogenerator rotor supports", "mining hoist and winder shafts" ], "failure_modes": [ "inner-ring raceway spalling from overload or contamination in the line-contact hertz zone", "outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating", "cage pocket wear from roller skew at light load", "polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant", "roller-end scoring from inadequate oil flow in the roller-raceway contact", "edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit", "brinelling from static overload or impact during handling and mounting" ], "pitfalls": [ "Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing", "The dimension series 39 (compact OD) envelope is shared with the N/NU/NJ/NUP executions of 3992, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 3992 ECMA and do not substitute rib styles without checking the shaft locating scheme.", "Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 620 mm raceway.", "Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 118 mm-wide ring and concentrates load.", "The 2050/4550 kN ratings are SKF catalogue 17000 (2018) values for the ECMA execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification." ], "faq": [ { "q": "What are the dimensions and catalogue data of NUP3992-ECMA?", "a": "SKF NUP 3992 ECMA is a single-row caged cylindrical roller bearing with 460 mm bore, 620 mm OD and 118 mm width per ISO 15. SKF lists C 2050 kN, C0 4550 kN, Pu 375 kN, reference speed 850 r/min and limiting speed 1,300 r/min, mass about 112000 g." }, { "q": "What does the NUP designation and ECMA suffix mean?", "a": "The ECMA suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring." }, { "q": "Can NUP3992-ECMA take axial load and locate the shaft?", "a": "Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance." }, { "q": "How does NUP3992-ECMA compare with the other executions in the same envelope?", "a": "The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number." }, { "q": "What limits the service life of this bearing most often?", "a": "Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers." } ], "cross_ref": [ { "equiv_sku": "NUP3992", "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/roller-bearings/cylindrical-roller-bearings", "catalog_ver": "SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings", "extracted_at": "2026-09-26", "last_verified": "2026-09-26", "confidence_score": 0.7, "status": "published", "aliases": [ "NUP3992-ECMA", "SKF NUP 3992 ECMA" ], "locale_variants": {} } ]